Features: Stainless Steel Locking Ball Ensures Secure Fit Sockets Snap-On Tightly & Won'for t Slip Off 1/4-inch Hex Shank Prevents Stripping During High Speed Drill Operation Super Strong Heat Treated Chrome Vanadium Steel for Normal & Impact Use - sandblasted finish Converts power drills into speedy socket drivers Applies to the screwdriver handle or electric screwdriver tools (hexagonal hole or three jaw chuck can be) Driven sleeve is used, can be the original hexagonal side after installation on size into square size, which can be used for the installation of the sleeve, is a good accessories to convert Specification: Material: Chrome Vanadium Steel CR-V Color: Black Size: (approx.) 1/4" x 1/4" x 50mm--1/4 "shank can be converted into 6.35 mm square 3/8" x 1/4" x 50mm--1/4 "shank can be converted into 9.53 mm square 1/2" x 1/4" x 50mm--1/4 "shank can be converted into 12.7 mm square Quantity: 1 Set/3 Pcs Note: Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Contents: 3 Pcs x Hex Socket Bits