The extension tube made from gray solid PVC + black rubber cover, suitable for protection against dust and water during rain (because of the small hole for cable, there is no longer protection IP67).
The extension tube is designed for floor boxes STAKOHOME-7701-A/Anw/H/Hnw, STAKOHOME-7601-A/Anw, STAKOHOME-7602-A/Anw, STAKOHOME-7501-A/Anw.