GKH device installation duct made of halogen-free PC/ABS, suitable for mounting directly on the wall or on wall brackets. Fastening is done via the standard holes in the duct. The GKH device installation duct has a C-profile on the bottom to accommodate a plastic partition. All switch ranges in support ring and support bracket design as well as module 45 installation devices can be installed in the device installation boxes of the 71GD... series. The system opening is 76.5 mm. A pair of couplings is pre-mounted on one side for each duct length.