The RAP-B-400-GA63U consists of the small Tough-Claw base, double socket arm and Garmin VIRB camera adapter. The RAM Tough-Claw is the perfect mounting base for quick and easy tool-less installation and removal on round, square, odd shaped rails and bars. The Tough-Claw can be clamped on rails from 0.625″ - 1.5″ outer diameter. The mount is designed with a RAM 1″ diameter patented rubber ball and socket system that has adjustment points at both ends of the double socket arm; this allowing for almost infinite adjustment and perfect viewing angles. The adapter attaches directly to the under-side of the camera, replacing the factory mounting bracket. Clamping Range (Rail/Tube Surfaces): 0.625″ to 1.5″ Clamping Range (Flat Surfaces): 0″ to 1.14″