Easy- Snap Fit Diffuser. Medium to Wide Light Dispersion. Available in 1m or 2m LengthsExternal Cross Section: 20 x 20mm Internal Cross Section: 16 x 13mm Diffuser Visible Width: 20mm. Extruded aluminium channel profile for LED tape installation. Supplied with clip in round diffuser- end caps and clips for mounting onto walls or ceilings. This profile provides an illuminated rail effect with medium to wide light dispersion.. led strip profile-led strip fixing-led tape profile