A Continuous Line of Light,
Only 3mm Wide
The NLL-400D is a COB LED strip on a 3mm board. It produces a smooth, dot-free glow with CRI above 90, so it can sit in the narrowest slots in joinery, shelving and slim profiles without showing individual LEDs.
Narrow Spaces Are Where Dots Show Most
The slimmer the slot, the closer the diffuser sits to the LEDs, and the harder it is to hide them. A conventional strip in a shallow 3mm groove will usually show a row of bright points. That is fine in a hidden cove, but not on a shelf edge, a wardrobe upright or a display plinth where the light line is part of the design.
COB (chip-on-board) construction solves this at the source. Instead of separate LED packages with gaps between them, a dense row of small chips sits under one continuous phosphor coating. The strip emits a single, even line — visible directly or through the thinnest diffuser.
The NLL-400D puts that output on a 3mm PCB with CRI above 90 and a 3000K warm white tone, so timber, stone, fabric and finishes look as they should.
NLL-400D-COB at a Glance
Cut Every 2cm — Fit the Joinery, Not the Other Way Round
Shelves, niches and cabinet frames rarely come in neat multiples of 5cm or 10cm. With a cut point every 2cm, the NLL-400D can run almost exactly to the edge of each piece, so there is no dark gap at the end of the line and no need to adjust the carpentry to suit the strip.
Built for Detail Work
Everything about the NLL-400D is aimed at the places where the light line is seen, not hidden.
Dot-Free Output
COB construction gives one continuous line of light with no visible LED points, even without a deep diffuser.
3mm Board
Fits ultra-narrow slot profiles and routed grooves that standard 5mm and 8mm strips cannot use.
CRI Above 90
Materials, finishes and products are shown in accurate, natural colour.
3000K Warm White
A warm, comfortable tone suited to homes, hospitality and premium joinery.
2cm Cut Points
Fine cutting resolution for accurate fitting to cabinets, shelves and niches.
10W/m Output
Enough brightness for task and accent lighting, with straightforward power supply sizing.
Applications
Wardrobe Uprights
Vertical light lines inside wardrobe frames that light clothes evenly.
Shelf Front Edges
A clean glowing edge on glass or timber shelves, visible without dots.
Under-Cabinet Lines
Even task light on counters with accurate food and surface colours.
Display Cases
Slim lines inside showcases for jewellery, watches and accessories.
Headboards & Niches
Warm accent lines in hotel rooms and suites.
Stair Treads
Thin recessed guide lines in steps and handrails.
Vanity Mirrors
Dot-free backlighting in dry zones behind mirrors and vanities.
Plinths & Alcoves
High-CRI light for artwork and objects in narrow recesses.
Bed & Sofa Bases
Soft floating glow under beds and seating.
Slim Linear Grooves
Fine light lines routed into gypsum or panelled ceilings.
Counter Edges
A continuous warm line along bar fronts and back shelves.
Reception Desks
Precise accent lines on reception and feature joinery.
Four Steps to a Clean Line
A good result depends as much on preparation as on the strip itself.
Choose the Profile
Use a slim aluminium profile or routed groove with a base of at least 3mm, to manage heat and keep the line straight.
Measure and Cut
Measure each run and cut only on the printed marks, which fall every 2cm.
Connect Properly
Solder leads to the pads for concealed work. On longer runs, feed power from both ends.
Size the Driver
10W/m × total length + 20% headroom. One 5m roll (50W) suits a 60W power supply.
Pair It With the Right Profile and Power Supply
Nucleo supplies slim aluminium profiles, diffusers and compact power supplies to go with the NLL-400D, including options that fit inside wardrobes and cabinets. Share your run lengths and we will put together a matched kit.
Frequently Asked Questions
An SMD strip mounts individual LED packages with gaps between them, so each one can show as a bright spot through a shallow diffuser. A COB strip bonds a dense row of tiny LED chips directly to the board and covers them with a continuous phosphor layer, so the strip emits an unbroken line of light. The NLL-400D gives a smooth line even when it is seen directly or used with a very shallow diffuser.
The 3mm PCB fits ultra-narrow slot profiles, coin-edge and mini recessed channels, and grooves routed into joinery, which are too narrow for standard 5mm or 8mm strips. Make sure the internal base of the profile is at least 3mm wide so the strip sits flat. Always use an aluminium profile for heat management, especially over longer runs.
The strip can be cut every 2cm at the marked cut points on the PCB. The short interval lets you match shelf, niche and cabinet dimensions closely without leaving an unlit gap at the end of the run. Cut only on the marked lines, between the copper pads.
The strip draws 10W per metre. Multiply by the total length and add about 20% headroom. A full 5m roll is 50W, so a 60W power supply suits one roll. Match the power supply output voltage to the voltage marked on the strip, and choose a dimmable driver if the lighting needs to be dimmed.
CRI measures how accurately a light source shows colours compared with natural light. Above 90, wood grain, fabric, skin tones, food and artwork look natural rather than flat or greenish. That makes the NLL-400D suitable for wardrobes, retail displays, kitchens and gallery niches where materials and colours are on show.
Soldering leads to the copper pads gives the most reliable, low-resistance joint, and is recommended for concealed installations. Solderless connectors made for 3mm strips can be used on short, accessible runs. For long runs, feed power from both ends to keep the brightness even along the line.
The NLL-400D is intended for dry indoor use such as joinery, ceilings, shelving and displays. For bathrooms, outdoor areas or anywhere exposed to moisture, use a waterproof IP65 or IP68 strip instead.
Planning Slim Light Lines?
Send us your joinery drawings or run lengths. We'll confirm quantities, profiles and the right power supply for the NLL-400D.
