The RAM-B-400-A-366U consists of the RAM® Tough-Claw™ rail clamp base, short double socket arm and 1/4"-20 threaded ball adapter for action cameras. 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 RAM® Tough-Claw™ can be clamped on rails from 0.625" - 1.5" outer diameter.