Smart Drive 90 is an advanced gunsmithing driver set. The main driver features a magnetic bit holder, rubber grip, jewelers spin top & 360 degree LED light. It partners with the small close quarters driver to create Force Assist. Force Assist is a proprietary system that helps users to loosen frozen-in-place screws as well as precisely tighten screws. Features : Magnetic Bit Holder Rubber Grip 360deg LED Light