Milwaukee 48-32-1700 Insert Bit Screw Driving Set - 20-PieceDesigned for quick change applications. Crafted from high grade S2 tool steel which provides excellent wear resistance for long life. The magnetic drive guide reduces fastener slipping and wobble by holding long fasteners in place while the sleeve retracts as the screw is driven into the material. Includes magnet on underside of case allows it to be attached to most metal tool boxes, job storage boxes, truck boxes or other metal surfaces for quick,