Impact Grade Nut Setters With Industrial Strength Magnets This Magnetic Impact Nut Driver Set will turn your high-torque power drill into a high-speed power nut driver for your next impact grade project. Our nut drivers come coated in Manganese Phosphate and are made from heat-treated Chrome Vanadium steel, so they can be used with your power drill on high-torque projects. The industrial strength magnets mean you'll get superior bit retention, so you don't have to worry about losing them while you work. Features: Set includes: 3 pc. nut drivers Size: 5/16-inch 1/4-Inch Hex Shank Length: 1 3/4-inch Made of heat treated Chrome Vanadium steel Converts power drills into nut drivers Manganese Phosphate coating Industrial strength magnets for superior bit retention