Makita Magnetic HEX NUT DRIVER (METRIC, MM) 5PC/SET B-39176 Standard Screwdriving bits are brittle and fit Poorly into fasteners, and in applications with high torque impact drivers this losing Combo quickly leads to broken bits. Precision machined (not forged) tips ensure full contact fit, while performance-optimized and heat-treated S2 steel provides more flex and more durability than standard, brittle bits. Professionals require commercial duty bits and fastening accessories that can endure the force of high-volume screw driving applications with high torque impact drivers. Professional Nut Driver Dottie L.H. Dottie 3/8'' X 1-3/4'' Magnetic Nut Driver (Carded) MT38C Makita Nut Driver Features. Magnetic nut driver provides convenient pick-up and retention of hex fasteners; lobular design drives along flats to reduce rounding of hex... Flat edges at hex opening for full contact with flanged hex head screws Impactx is a line of impact-rated insert bits and fastening accessories built specifically for the demands of the professional contractor. Erbauer Hex Shank Impact Nut Driver 13mmx65mm Performance-optimized S2 steel construction for extended life