A narrow smooth strip remained between the slat panels: how to assemble a decorative vertical from MLDPU-003 molding and NPU-399.1 central overlay 76 × 202 mm

If two slat panel zones are separated by a narrow smooth strip, this strip has three fundamentally different scenarios. It can be left completely empty, turning it into a visual pause. You can try to assemble a full molding frame inside, but at a width of about 300–400 mm it often turns out too busy. The third option is to run one vertical MLDPU-003 line and place one central NPU-399.1 accent on it.

This particular option is interesting because it does not require assembling a composition from many parts.

The basic set consists of two main decorative items:

• molding MLDPU-003 measuring 35 × 12 × 2600 mm — 7,580 ₽;

• central overlay on the molding NPU-399.1 measuring 76 × 202 × 21 mm — 3,390 ₽.

Total:

7 580 + 3 390 = 10 970 ₽.

If you add KUDO HIGH TACK costing 990 ₽, which is listed among related products, the total comes to 11,960 ₽ excluding delivery and other expenses. For the long-length MLDPU-003, the card also separately lists a rigid packaging frame costing 390 ₽, so this expense should be taken into account when finalizing the cart.

But buying a combination just because two items are compatible is not worth it. First, you need to resolve five practical questions:

1. whether one MLDPU-003 strip is enough for the actual height of the decorative vertical;

2. whether NPU-399.1 is too active for the specific width of the smooth strip;

3. where the central overlay should be located — at the geometric center or with a visual offset;

4. how the 21 mm relief looks between two textured slat zones;

5. does stucco actually improve the wall, rather than removing a useful visual pause.

Only after this does it make sense buy central overlay NPU-399.1 и buy polyurethane molding MLDPU-003 as one calculated composition.

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Why one vertical can work better than a full frame

A narrow smooth strip between slatted zones is itself a strong geometric situation.

On the left, there is already a set of vertical lines. On the right, a second set. If you build a rectangular frame inside the free field, additional ones will appear:

• two verticals;

• two horizontals;

• four corners;

• Inner frame field.

On a wide wall, such a pattern can be appropriate. On a narrow insert, it can turn a small architectural pause into an overloaded set of borders.

One MLDPU-003 line works differently.

It does not try to create another separate "wall within a wall" inside the strip, but rather emphasizes the existing vertical direction.

The central NPU-399.1 solves the second task: the straight line no longer looks like a randomly attached profile and gains a compositional center.

The result is a sequence:

slats → smooth field → thin central vertical with one decorative point → smooth field → slats.

This differs significantly from the frame both in pattern and in the number of purchased parts.

But it is precisely because of the simplicity of the composition that errors become more noticeable. If the single vertical is shifted a few centimeters without reason or NPU-399.1 is installed too high, there is nothing else to distract attention with.

Therefore, such a scheme requires precise preliminary marking.

What exactly we buy: NPU-399.1 and MLDPU-003

NPU-399.1 should be called correctly — central molding overlay.

Its confirmed specifications:

Parameter	NPU-399.1
Product type	Central overlay for molding
Size	76 × 202 × 21 mm
Material	Polyurethane
Price	3,390 ₽/pc.
Sale	From 1 pcs.
Production	Custom Order
Average production time	3–7 days

Card:

buy central overlay NPU-399.1

Linked profile — MLDPU-003.

Parameter	MLDPU-003
Product type	Polyurethane molding
Size	35 × 12 × 2600 mm
Material	Polyurethane
Length of one plank	2600 мм
Price	7 580 ₽

Card:

buy polyurethane molding MLDPU-003

The connection between the two items is confirmed by the catalog itself: NPU-399.1 is shown together with MLDPU-003, and the molding, in turn, offers NPU-399.1 among related elements.

This is useful for the buyer: there is no need to independently select a trim for a random profile based on a roughly similar size.

Our factory also produces:

View Full Product Catalog

First, calculate not the room height, but the actual length of the decorative line

MLDPU-003 is supplied as a strip 2600 mm long.

This raises a simple but important question:

Is one strip enough for your vertical?

You cannot automatically compare 2600 mm with the full height of the room.

The molding can start:

• above the floor baseboard;

• from the top edge of the low panel;

• from the countertop;

• from the console;

• with a decorative gap from the floor.

At the top, it also does not have to reach the ceiling. There may be:

• ceiling cornice;

• shadow profile;

• top gap;

• another stucco detail.

Therefore, the working length of the vertical is needed.

Formula:

L = H − B − T,

Where:

• H — actual wall height;

• B — lower occupied or reserved zone;

• T — upper occupied or reserved zone.

For example, only as a calculation method:

• room height — 2700 mm;

• from below, 80 mm is occupied or reserved;

• from above — 120 mm.

We get:

2700 − 80 − 120 = 2500 mm.

For a vertical of 2500 mm, one MLDPU-003 plank with a nominal length of 2600 mm is sufficient.

remains:

2600 − 2500 = 100 mm

before accounting for actual trimming.

This is already a real calculation before purchase.

When one MLDPU-003 plank is enough and when it is not

The condition for one continuous vertical is simple:

working length ≤ 2600 mm.

Working length of the vertical	MLDPU-003 plank	What to Check
2200 мм	1	Position of the top and bottom ends
2400 мм	1	Is there enough mounting allowance
2500 мм	1	Precise trimming and actual length
2600 мм	1 nominally	Cannot rely on length allowance
more than 2600 mm	1 insufficient	A second plank, a joint, or a change in composition

The last line is fundamental.

If the actual vertical should be, for example, 2650 mm, you cannot write:

“one plank almost fits.”

It is short by 50 mm.

Next, a separate decision needs to be made:

• buy a second plank;

• providing for a joint;

• shorten the decorative vertical;

• change the top or bottom margin;

• choose a different design principle.

For a narrow strip between battens, it is often wiser to slightly reduce the length of the composition and leave intentional margins rather than create an extra intermediate joint just to fill the entire height.

But this is already a visual decision for a specific wall.

Do not automatically subtract 202 mm NPU-399.1 from the molding length

This is a separate error that may occur when ordering.

One of the dimensions of NPU-399.1 is 202 mm.

The buyer may decide:

"If the overlay is in the middle, then 202 mm must be subtracted from the total length of MLDPU-003."

This cannot be done without an installation diagram.

NPU-399.1 is called a molding overlay, not an independent profile segment that automatically replaces 202 mm of MLDPU-003.

Therefore, the safe calculation logic is as follows:

1. first, determine the full length of the MLDPU-003 line;

2. separately, determine the location of NPU-399.1;

3. check the actual connection point of these components on the product;

4. only after that decide whether any cutting or trimming of the straight profile itself is required.

Do not reduce the MLDPU-003 order just because of the length of the central decorative element.

How to find the correct axis of the smooth strip

If the smooth insert is located strictly between two identical zones of slat panels, its geometric center becomes the first candidate.

Suppose the actual width of the free field is 360 mm.

The central axis is at a distance:

360 / 2 = 180 mm

from each boundary.

It is along this line that you can preliminarily mark the vertical for MLDPU-003 with painter's tape.

But the geometric center is not an absolute rule.

It may not coincide with the visual center of the room if:

• the slat zones on the left and right are of different widths;

• a doorway is located nearby;

• furniture is shifted;

• the ceiling light has its own axis;

• One side of the wall is partially covered by curtains.

Therefore, there are two stages.

First, geometry

The physical middle of the smooth strip is found.

Then visual check

Look at the entire wall from the main viewpoint.

If the line seems shifted only because neighboring objects are asymmetrical, you can check the second layout option.

But the shift must have a reason. Randomly moving the molding by 20–30 mm "until it looks right" without understanding the entire composition is a bad approach.

How to check NPU-399.1 on a strip 300–400 mm wide

The size of NPU-399.1 is confirmed as 76 × 202 × 21 mm.

At the same time, you cannot automatically assume the first dimension is the horizontal width just from the order of dimensions in the record. Before precise horizontal calculation, you need to verify the actual orientation of the element from the product card and image.

If in the selected vertical orientation 76 mm indeed corresponds to the horizontal, the free space can be preliminarily estimated.

For a 300 mm strip:

(300 − 76) / 2 = 112 mm

on each side.

For a 400 mm strip:

(400 − 76) / 2 = 162 mm.

This looks quite spacious on paper, but the numbers do not yet show the actual expressiveness of the ornament.

A 1:1 template in the actual orientation of NPU-399.1 needs to be made and attached to the future MLDPU-003 line.

This checks not only the physical fit of the part, but also its scale relative to the rails.

Why a single drawing of 76 × 202 mm is insufficient

A flat paper rectangle only checks the silhouette.

The NPU-399.1 has a relief of 21 mm.

The MLDPU-003 profile has a depth of 12 mm.

That is, the central decorative part protrudes more than the straight profile according to these confirmed dimensions.

The difference:

21 − 12 = 9 mm.

This is normal for a central accent: it should read more expressively than the main line.

But nearby there are also slats that create their own depth and repeating shadow.

Therefore, the flat paper template should be supplemented with a simple three-dimensional mockup.

For example:

• a cardboard rectangle of the desired silhouette;

• a spacer simulating protrusion;

• painter's tape instead of MLDPU-003.

Look at the wall at an angle.

If the central overlay looks too massive against the narrow strip, the problem will be detected before purchase.

Where to place NPU-399.1 in height

There is no universal height like "1200 mm from the floor" here.

Such a number without reference to the wall would be artificial.

There are three reasonable ways to start the fitting.

Geometric center of the decorative line

If MLDPU-003 has a working length of 2400 mm, the middle is at the 1200 mm mark relative to the start of the line itself.

This is a neutral starting point.

Visual center of the visible part of the wall

If the lower zone is covered by a console or a dresser, the mathematical center may end up too low.

Then the overlay should be evaluated relative to the actually visible area.

Alignment with an adjacent object

Sometimes NPU-399.1 makes sense to align by height with:

• the center of a painting;

• with a horizontal line of furniture;

• wall sconce;

• a decorative band on the adjacent wall.

But such a binding should improve the composition, not create a random grid.

The best way is to cut out one full-size template of NPU-399.1 and take three photos:

• in the geometric center;

• slightly higher;

• slightly lower.

From one viewpoint, the difference becomes more obvious than when constantly moving the template near the wall.

One NPU-399.1 or two on the same vertical line

The basic scheme of the article is one central overlay on one MLDPU-003 line.

It is in this layout that NPU-399.1 serves as the center of the composition.

The second overlay completely changes the pattern.

Instead of:

line → center → line

It turns out:

line → accent → section → accent → line.

On a tall, wide wall, such repetition may be appropriate.

On a narrow insert between slat panels, two identical large decorative dots can make the vertical too saturated.

Therefore, the number of NPU-399.1 units cannot be chosen based on the principle:

"two are more symmetrical than one."

One central overlay already has its own symmetrical function.

If after laying out one detail the vertical seems empty at the top and bottom, first check:

• the length of the MLDPU-003 itself;

• the position of NPU-399.1;

• the top and bottom margins;

• Color.

And only then add the second decorative part.

How MLDPU-003 works between vertical slats

Here two line systems meet.

The slat panel consists of many repeating verticals.

MLDPU-003 is one central vertical.

If all elements are equally active in color and contrast, the central line may get lost among the slats.

If made too contrasting, on the contrary, it will start dividing the wall into two independent parts.

Therefore, it is useful to decide what function the smooth strip performs.

This is a pause between two slat arrays.

Then MLDPU-003 is better made relatively calm, so that it does not destroy the very idea of a pause.

This is the central axis of the entire wall.

Then the line can be more expressive, and NPU-399.1 becomes the main accent.

This is a transition between different zones of the room.

Then the molding can mark the boundary, but its position is no longer determined solely by the middle of the strip.

That is why the same combination of MLDPU-003 + NPU-399.1 can look appropriate on a 3 m wall and completely unnecessary on another wall with the same physical dimensions.

Color: combine the molding and the overlay or make an accent.

Color noticeably changes the strength of the central vertical line.

MLDPU-003 and NPU-399.1 in the color of the wall.

The calmest option.

The molding and the overlay are read through relief and shadow.

If there are noticeable wooden or contrasting slats nearby, this option allows keeping the smooth strip visually light.

In the color of the slat panels

The central vertical line begins to connect two slatted zones.

This can be interesting if the task is not to break them apart, but to create a compositional connection through a smooth insert.

Molding in the wall color, NPU-399.1 contrasting

Then the small central element becomes a separate decorative point.

This solution requires caution: NPU-399.1 has a relief of 21 mm and, even without a contrasting color, can be read well in side light.

Fully contrasting vertical

MLDPU-003 and NPU-399.1 become a separate graphic axis.

In a narrow strip, this option changes the wall architecture the most.

Therefore, it is better to test it on a full-size color mockup rather than on a small sample.

Do not confuse NPU-399.1 and NPU-399

With similar article numbers, there is a real risk of error when searching and ordering.

NPU-399.1 from our composition:

• 76 × 202 × 21 mm;

• polyurethane;

• central overlay;

• considered together with polyurethane MLDPU-003.

There is another element — NPU-399.

In the CPU-1-1 kit, it has the following dimensions:

77 × 183 × 21 mm

and is used with MLD-003-MG, which already refers to primed MDF.

That is, these are two different systems.

Parameter	NPU-399.1	NPU-399
Size	76 × 202 × 21 mm	77 × 183 × 21 mm
Overlay material	Polyurethane	Polyurethane
Associated profile in the system under consideration	MLDPU-003	MLD-003-MG in CPU-1-1
Profile material	Polyurethane	Primed MDF

The difference in the name is just ".1", but for the order it is fundamental.

You cannot take the dimensions of NPU-399 and use them to calculate space for NPU-399.1.

And you cannot automatically transfer the mounting diagram of one system to another.

How much does one decorative vertical cost

Basic set:

Position	Quantity	Price	Total
MLDPU-003	1 slat	7 580 ₽	7 580 ₽
NPU-399.1	1 pc.	3 390 ₽	3 390 ₽
Total decorative items			10 970 ₽

If you add KUDO HIGH TACK:

10 970 + 990 = 11 960 ₽.

For MLDPU-003, a rigid packaging frame of 390 ₽ is specified separately.

If this expense applies to your order:

11 960 + 390 = 12 350 ₽

before delivery and other possible costs.

Such a breakdown is more useful than the general phrase "the composition costs about 12 thousand," because it immediately shows what part of the budget goes to decor, what to the mounting compound, and what to the packaging of the long-length profile.

What happens if two identical verticals are needed

Sometimes smooth inserts are located not in one, but in two places in the room.

Then the base decorative part is doubled:

• 2 × MLDPU-003;

• 2 × NPU-399.1.

Cost:

2 × 10 970 = 21 940 ₽

before glue, packaging, and delivery.

But you cannot automatically double the order.

First, measure each strip separately.

They may differ:

• by actual height;

• in width;

• by position relative to furniture;

• on lighting.

In one zone, the central overlay may look appropriate, while in the second, the vertical is partially covered by a cabinet.

If two compositions are not visible simultaneously, strict identity may not be needed at all.

How to check the bottom and top endings of MLDPU-003

The central overlay draws attention to the middle, but poorly finished molding endings can ruin the entire vertical.

At the bottom, you need to decide:

• does MLDPU-003 fit the baseboard;

• ends above it;

• goes behind furniture;

• has an independent offset.

At the top:

• does the line reach the ceiling cornice;

• ends lower;

• connects with another profile;

• remains independent.

If both ends are free, they should look intentional.

This is especially noticeable with a short vertical where the top and bottom are simultaneously in view.

You don't need to first glue the entire 2600mm strip and then decide where it should have ended.

First, mark out the entire line.

Should MLDPU-003 be extended to the floor and ceiling

No.

The physical length of the strip being 2600mm is not a requirement to use all 2600mm.

If the wall is 2700 mm high, you can make a decorative line, for example, shorter and leave margins.

Such a composition sometimes even better highlights NPU-399.1 as an independent central element.

But the indents cannot be chosen separately from each other.

Check:

• the height of the baseboard;

• top decoration;

• center of NPU-399.1;

• visibility of the entire vertical.

Often after this it becomes clear that filling the wall "from edge to edge" is not required at all.

How to prepare a full-size mockup

For this composition, a mockup can be made almost for free.

You will need:

• masking tape;

• tape measure;

• level;

• paper or cardboard;

• photo or diagram of NPU-399.1.

Step 1. Draw a vertical line MLDPU-003

Using tape of a width that approximately shows the profile, mark the future line.

Step 2. Mark its actual beginning and end

Do not automatically use the entire height of the wall.

Step 3. Make a template NPU-399.1

Size — according to the actual orientation of the product at a 1:1 scale.

Step 4. Place the template in the geometric center

Take a photo.

Step 5. Move up

The second photo.

Step 6. Move down

Third.

Step 7. Look at the wall with the evening light on

The relief near the battens may be perceived differently.

Step 8. Check from the side

Especially the 21-millimeter volume of the central overlay.

Only after such a mockup can the size and position truly be considered approved.

When it's better to leave a smooth strip without molding

Empty space is also a design tool.

MLDPU-003 and NPU-399.1 should be abandoned if the smooth strip already performs a useful pause function.

For example:

• Slat panels have an active pattern;

• there is a lot of other decor on the adjacent wall;

• The central insert is very narrow;

• Expressive furniture stands in front of it;

• a switch or other equipment is located inside the strip;

• the molding line competes with vertical seams;

• NPU-399.1 visually makes the composition too classic for the chosen interior.

Under such conditions, purchasing additional decor does not improve the wall.

This is a normal result of the fitting.

When instead of a single vertical line, it is better to create a full composition

The opposite situation — the smooth field turned out to be much wider than expected.

On a strip of 300–400 mm, a single line may be sufficient.

If the free central zone is significantly wider, a single MLDPU-003 sometimes starts to look too thin.

Then you can consider:

• a frame;

• two parallel verticals;

• larger wall decor;

• a ready-made vertical composition.

For such options, it is useful to look at buying polyurethane molding decor or a broader section Buy polyurethane wall decor.

The task is not to necessarily use NPU-399.1, but to match the scale to the specific architecture.

Errors in ordering and marking

Error 1. Buying MLDPU-003 before calculating the working height

The plank is 2600 mm, but this does not indicate the actual length of your vertical.

Consequence: one plank may not be enough, or a large unnecessary remainder will be left.

How to avoid: first calculate H − B − T.

Error 2. Subtracting the 202 mm overlay from the length of the molding

NPU-399.1 cannot be automatically considered a replacement for a section of MLDPU-003.

Consequence: the ordered straight profile may turn out shorter than necessary.

How to avoid: count the MLDPU-003 line completely, and check the mounting unit of the overlay separately.

Error 3. Taking 76 mm as horizontal width without checking orientation

The order of recording dimensions by itself does not prove orientation.

Consequence: erroneous calculation of side margins.

How to avoid: before calculating, verify the actual orientation of NPU-399.1 according to the card.

Error 4. Installing the overlay "approximately in the middle"

On one central line, even a small random shift is clearly noticeable.

How to avoid: first mark the geometric center and compare it with the visual one.

Error 5. Not checking the depth of 21 mm

From the front everything looks neat, but from the side NPU-399.1 starts competing with the relief of the slats.

How to avoid: a volumetric mockup and viewing at an angle.

Mistake 6. Automatically buying two NPU-399.1

Two parts are not a "more correct" version of one.

How to avoid: first evaluate one central overlay.

Error 7. Confusing NPU-399.1 with NPU-399

The article numbers are similar, but the sizes and related systems are different.

How to avoid: check the full article number, size, and molding before adding to cart.

Mistake 8. Making a vertical just because the smooth strip seems empty

The emptiness could have been intended as a visual pause.

How to avoid: be sure to compare two photos of the layout — with and without the molding.

What to add to the cart

For one basic vertical:

Main molding

buy polyurethane molding MLDPU-003

Quantity:

1 plank, if the calculated continuous line fits within 2600 mm considering the actual trimming.

Central overlay

buy central overlay NPU-399.1

Base quantity:

1 pc.

Mounting compound

buy glue for installing moldings

The quantity needs to be determined based on the actual installation technology and the base.

If NPU-399.1 does not match the pattern or scale, you can look at buying polyurethane molding decor.

For another profile — buy polyurethane moldings.

A broader catalog — You can buy ready-made stucco matching the Baroque style. Calculate the quantity: linear meters of cornices and moldings, number of rosettes, pilasters, consoles, corner elements. Add a ten to fifteen percent allowance for trimming..

If the textured wall zones themselves are still being designed, you can first Buy slatted panels for wall finishing and only after determining their actual width calculate the remaining smooth insert.

Practical algorithm before ordering

1. Measure the actual width of the smooth strip between the slat zones.

2. Measure the wall height.

3. Determine the lower occupied or free zone.

4. Determine the upper zone.

5. Calculate the working length of the vertical.

6. Compare it with the length of MLDPU-003 — 2600 mm.

7. Find the geometric axis of the smooth insert.

8. Mark the future MLDPU-003 with painter's tape.

9. Verify the actual orientation of NPU-399.1 against the card.

10. Make a template of the overlay at a 1:1 scale.

11. Check the central, higher, and lower positions.

12. Look at the composition from the front and from the side.

13. Compare the wall with and without NPU-399.1.

14. Make sure NPU-399.1 and NPU-399 are not mixed up.

15. Calculate the final cart.

16. Only after that place the order.

For the standard scenario with one vertical that fits into a single 2600 mm rail, the base purchase is:

1 × MLDPU-003 + 1 × NPU-399.1 = 10 970 ₽.

Decision table

Situation	Solution
Working vertical shorter than 2600 mm	Check whether one MLDPU-003 is enough considering cutting
Working vertical exactly around 2600 mm	Do not assume that the strip has extra allowance
Vertical longer than 2600 mm	Need a different scheme, joint, or additional plank
The strip is narrow	Make template NPU-399.1 at 1:1 scale
The central overlay looks too massive	Leave only the molding or choose a different decor
One NPU-399.1 looks complete	Do not add a second one for symmetry
Two slat zones are too active	Check the calm coloring of the molding
The strip already works as a visual pause	You can leave it without molding
The article number looks like NPU-399	Re-check: NPU-399.1 is specifically needed
Layout confirmed	Form the cart

FAQ

What to do if the smooth strip at the top is narrower than at the bottom?

Do not rely on a single measurement. Measure the width at several points. If the discrepancy is noticeable, first determine the geometry of the wall and the slat zones, and only then determine the visual axis of the molding. Simply dividing the bottom width in half can result in a noticeably shifted line at the top.

Can NPU-399.1 be used if a door trim runs nearby?

This option can be considered, but the competition between the two decorative systems needs to be checked. If the casing already has an active ornament, a central overlay on a narrow strip may be redundant.

What to do if there is a switch in the smooth strip?

Do not try to automatically run the molding through electrical fixtures. First, determine whether the axis or length of the decorative line can be changed without compromising the composition. If the switch occupies the central part, the very idea of NPU-399.1 in the center may become unsuccessful.

Can NPU-399.1 be placed not at the geometric center, but at the level of the door handle?

Yes, if it is a deliberate visual alignment. But first compare this option with the geometric center in photographs. Aligning to a random door height does not always improve the entire wall.

What to do if one edge of the slat panel is closer to the molding than the other?

This means that the smooth insert or slat zones are asymmetrical. You need to decide what is more important: centering MLDPU-003 within the physical field or relative to the entire wall. There is no universal answer without specific architecture.

Can MLDPU-003 be made only in the upper half of the wall?

Yes, if the short line is an independent composition. But then NPU-399.1 no longer works as the center of a tall vertical, so its position needs to be reconsidered relative to the entire shortened line.

Can NPU-399.1 be placed below the center if there is a console in front of the wall?

Yes. Furniture changes the visible part of the wall. If the mathematical center turns out to be visually too low or partially hidden, the template should be moved and the new composition evaluated with the actual furniture.

What to do if MLDPU-003 has to be joined?

The joint should be designed separately and not placed randomly in the most visible part of the vertical. If it is possible to change the length of the composition and avoid an unnecessary connection, this should be compared with the option of an additional strip.

Can the remainder of MLDPU-003 from another frame be used?

Yes, if the actual length of the remainder covers the entire required vertical or the section specified in the project. The actual remainder after previous cuts should be calculated, not the original 2600 mm.

What to do if the central overlay looks nice during the day but is too active in the evening?

Check the side artificial lighting. With a relief depth of 21 mm, shadows may become stronger in the evening. Sometimes a calmer color or changing the position of the light source helps, rather than abandoning the composition itself.

Can NPU-399.1 be used without MLDPU-003 as a standalone overlay?

In this article, it is considered as a central overlay on a connected molding system. For standalone use without MLDPU-003, you need to separately check the card recommendations and composition; you cannot automatically transfer the calculations from this article here.

What to do if, after the mockup, one NPU-399.1 seems too small, but two seem too many?

This is a sign that the problem may not be in the number of overlays, but in the scale of the composition itself. It makes sense to look at a different central decor or switch to a larger ready-made vertical system.

Is it necessary to repeat the same vertical on all smooth strips in the room?

No. Repetition is useful if the zones are truly part of one architectural system. If one strip is near the door and another is hidden behind furniture, mechanical duplication may look formal.

What to do if the slat zones are made in different colors?

Then the central vertical becomes a connecting element between two different fields. Before painting the molding, it is better to make color swatches or at least a digital comparison of several options: in the wall color, in the color of one of the panels, and neutral.

Can MLDPU-003 and NPU-399.1 be ordered in advance while the slat panels are not yet installed?

Yes, but the accuracy of the project will be lower. For a narrow insert, the actual width after panel installation is critical. Even a small change in the outer slats can shift the axis and side margins, so it is safer to fix the geometry first.

Summary: for one narrow vertical, you basically need one MLDPU-003 and one NPU-399.1

If a smooth vertical strip remains between two zones of slat panels, it is not necessary to turn it into a complex frame.

A calmer composition can consist of just two main elements:

1 × MLDPU-003 35 × 12 × 2600 mm

и

1 × central molding overlay NPU-399.1 76 × 202 × 21 mm.

At current prices:

7 580 + 3 390 = 10 970 ₽.

With KUDO HIGH TACK for 990 ₽:

11 960 ₽.

If the specified rigid packaging frame of 390 ₽ is applied to order MLDPU-003, the total for these items will be 12,350 ₽ before delivery and other expenses.

But before buying, you need to check not only the price.

The main sequence is as follows:

measure the smooth strip → calculate the working height → check whether 2600 mm of MLDPU-003 is enough → find the axis → make a 1:1 template of NPU-399.1 → check the orientation → evaluate the 21 mm relief from the side → compare several positions → make sure NPU-399 is not mixed up → only then order.

If the line fits within one plank by actual length and one central overlay looks convincing, the basic set really remains very simple:

buy polyurethane molding MLDPU-003

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buy central overlay NPU-399.1.

If, however, the full-size mockup shows that NPU-399.1 is too active, two slat zones without it already create sufficient pattern, or one thin vertical gets lost in too wide a field, it is better to switch to Decor for polyurethane moldings and choose a different composition — or leave the smooth insert completely free.