FLADVINKEL WDKH 20X20 MM HVID RAL 9010The WDK wall and ceiling ducts made of lead free plastic are primarily used in industrial applications. The product series ranges from 7. 5 mm x 7 mm to 100 mm x 230 mm. Standard colours are pure white, cream, stone grey and light grey. A wide range of fittings allows installations almost anywhere. For duct depth 60 mm an accessory mounting box can be used to install switch and plug devices.