Socket AdapterMade of heat-treated hardened chrome vanadium steel (CR-V), high hardness, good durability and abrasion resistance. Impact Socket Extension Bars1/4", 3/8" and 1/2" square sockets, 8 different lengths to provide extra length to reach hard-to-reach spaces. Anti-Slip DesignSpring-loaded ball bearing on the head to ensure a secure lock in the hand screwdriver, drill or impact wrench, can prevent slippage during use. 1/4" Hex Shank Socket AdapterFits 1/4" quick-change chuck systems or directly into drill chucks, handheld screwdrivers, electric screwdrivers, air drills, etc. Wide ApplicationIdeal socket adapters for your drill, turn your power drill or impact driver into a versatile high-speed nut driver, perfect for DIY and general repairs. Specification Material: Chrome Vanadium Steel (CR-V) Surface Treatment: Black Oxide Coating Hex Shank Diameter: 1/4 inch (6.35mm) 1/4 inch Hex Shank for: 1/4 inch (6.35mm) Square Drive x 4pcs 3/8 inch (9.53mm) Square Drive x 2pcs 1/2 inch (12.7mm) Square Drive x 2pcs Package Included 8 x Socket Adapter socket