REXBETI 12 Piece Hex Head Allen Wrench Screwdriver Bit Set, 1/4 Inch One Size Product Details Brand: REXBETI Item Length: 3 Inches Material: S2 Steel Drive System: Hex Finish Type: Black Phosphate, Black oxide finish, Chrome, Painted, Steel Number of Pieces: 12 Manufacturer: REXBETI Part Number: REX-8998 Item Weight: 6.7 ounces Item model number: REX063 Size: One Size Style: hex bit set Finish: Black Phosphate, Black oxide finish, Chrome, Painted, Steel Pattern: hex bit set Measurement System: Inch Compatible Fastener Range: 0.25 inch Batteries Included?: No Batteries Required?: No Brand: REXBETI Item Length: 3 Inches Material: S2 Steel Drive System: Hex Finish Type: Black Phosphate, Black oxide finish, Chrome, Painted, Steel Screwdriver Bits in the Following Sizes 1/16, 5/64, 3/32, 7/64, 1/8, 9/64, 5/32, 3/16, 7/32, 1/4, 5/16 and 3/8 inch Drill bits made from high quality S2 steel material for ultimate durability, suitable for industrial use. Strong magnetic and high precision. each edge can be accurately locked screws, no damage to the screw and the screwdriver head Not only can you use the bits on hand tools, you can easily insert them to any 1/4 inch hex shank power drill to use The torsion zone is designed to absorb torque peaks, preventing breakage. This feature increases the life expectancy by ten times compared to standard bits.