We are Manufacture, True Quality, Well-packed, buy with confidence! Features: 1. The extrusion is designed for <21mm flexible or rigid LED strips 2. Surface mount for creating lines of light flush with the surface of walls and ceilings 2. The aluminium channel is widely used as interior lighting. 3. Easy Installation with all needed accessories (cover, end caps,screws). Specifications: Inner width: 21mm Length: 2.0M/Segment,10M total Material: High Quality Aluminium Waterproof type: Non waterproof Cover/diffuser: opal Assembly: 1.Fixed in the groove with fixing glue or fixing screws 2.Profile fastening wings covered with gypsum plaster Package includes: 20 x 2.0M LED aluminium channel (LED strip light is NOT included) 20 x 2.0M Cover/diffuser 40 x End caps 40 x Screws Related items you may interested: (search on amazon) - For Narrower Drywall LED Channel 12.5mm: please search "B07JZ2LWRK "