Material: Home Use Chrome Vanadium Steel - Specification: Socket Standard 1/4" Hex Shank to 1/4" 3/8" 1/2" Socket &amp; 1/4" shank can be converted to 1/4" 3/8" 1/2" square head.Easy to choose: Various color-coded rings, make it easy to choose the right one. Suitable for Screwdriver or power drill has quick change 1/4" chuck systems or straight into drill chucks. Change your hand tools socket sets into an impact/drive sockets. Included: 3-piece 1 /4" drive adapter, 3/8" drive adapter and 1/2" drive adapter and each with a 1/4 inch hex screwdriver socket wrench adapter set. Connector sockets / socket wrenches / socket bits / driver sockets to power cordless drills. These adapters come in handy for attaching a socket sets / ratchet sockets / socket wrench / ratchet universal socket wrench to an electric drill. < Purpose: This adapter set is designed to provide a secure lock-in addition to your existing tooling. Provides extra length to reach into a variety of hard-to-reach spaces. The spring ball lock ensures a snug fit into the driver's head to prevent slipping during use. Specially machined to fit securely in a handheld driver, drill or impact wrench. General Use: This 3-piece Hex Shank Bit Driver Extension Bar Set is designed to meet a variety of needs. Fits individually and securely in your drill chuck or hand driver. Consisting of your most common bit sizes 1/4", 3/8" and 1/3" with alternating shank sizes, it offers versatility and convenience whichever tool you choose to use. Great for DIY, household maintenance and most general repairs, not industrial work.