High quality adapter sockets: Each adapter is made from heat-treated chrome-vanadium steel and coated with manganese phosphate to resist rust and corrosion and ensure long life. Wide Application: Suitable for quickly changing 1/4 inch chuck systems or directly into drill chucks. Each cordless drill in an electric groove driver. Convenient for quickly driving in nuts, screws and fasteners etc. Spring-loaded ball bearing on head holds sockets firmly. Compatibility: Suitable for screwdrivers or power drills, features 1/4" quick change chuck systems or straight into drill chucks. Change your hand tool socket sets into impact/drive sockets. Specifications: 3-piece 1/4" drive adapter, 3/8" drive adapter and 1-piece drive adapter /2" and each with a set of 1/4 inch hex driver socket wrench adapters. So you can turn any drill into a power screwdriver with the extra reach. Specifications: 3-piece 1/4" drive adapter, 3/8" drive adapter, and 3-piece drive adapter. 1/2" drive and each with a set of 1/4 inch hex driver socket wrench adapters. So you can turn any drill into a power screwdriver with the extra reach. Color: Black Size: Square head size is 1/2" (12.7mm), 3/8" (9.5mm), 1/4" (6.35mm) Shaft Diameter: 6.35mm Hex Shaft Opposite Sides, Double R-Groove Package Quantity: Set of 3