Features and Benefits:Striking impact to drive spring-loaded handle to remove rounded and frozen screws;Designed to drive 12 degree rotation with each impact;High performance steel end cap designed for repetitive striking impacts;Ergonomic tri-lobe dual material handle provides the optimal balance of strength and efficiency;“Speed Zone” handle design for faster rotation in low-torque applications ;These new Bolt Biter screwdrivers offer the convenience of a standard screwdriver with the extraction abilities of a dedicated impact driver, loosening rusted, stripped, or other difficult-to-remove screws. Their high-performance steel handle end cap transfers impact shock to an internal mechanism the rotates the heat-treated alloy steel shaft 12 degrees when struck. High-strength tips are rust resistant and nickel-chrome plated.