SE is proud to present our 3Pc Power Extension Bit Set for Drills—a great way to add versatility to your power drills. This 3Pc power extension socket adaptor has a Hex bit for all power drill chucks. Unlimited uses in automotive, hardware, hobby, workshop, warehouse, garage and home. Driver sizes (inches): 1/4, 3/8, & 1/2. Average total length: 2-½ inches. Driver width: ¼-inch. Chrome vanadium steel. Heat-treated steel. Ball-bearing lock. Turns any power drill into a power nut driver.