Custom ball end hex bit designed to tighten hard to reach screws. 3/16″ for Remington 700, AICS, etc. Shaft of bit is 0.1875″ X 4.0″ long for hard to reach screws. Works with any standard 1/4″ bit driver Integrates perfectly with Fix It Sticks Replaceable Edition for field / travel use. Integrates perfectly with T-Way Wrench for shop use.