Style: Flat Ceiling Adapter - Black QG-PRO-PM-CA-B single joist ceiling Adapter with cover can mounts to any wood joist, structural wood or structural concrete. This single joist ceiling Adapter is compatible with all standard 1. 5" npt threaded pipes that weights up to 80Lb and works with qg-pro-pm-50-b or qg-pro-pm-50-w projector mount.