Works with a 1/4" quick-change chuck system or directly inserts a drill chuck/turns any electric/cordless drill into a handheld/electric nut driver for fast nut driving, bolts and screw fixings etc. Holds the socket firmly. [Included] 3 Piece 1/4 3/8/1/2" Extension Kit and 4 1/4 Outlet Adapters to 3/8 - 3/8 to 1/4" - 3/8 to 1/2 - 1/2 to 3/8. Whatever tool you choose to use, it offers versatility and convenience.Ideal for DIY, home maintenance and most general repairs, not for industrial work.A great addition to any toolbox. Adapter set 1/4 - 1/2" 4 pieces (connectors) Suitable for all types of ratchets, ratchets, socket wrenches, torque wrenches, handles, etc. Passivated design: Passivated end facilitates quick installation and removal. describe: High quality material, strong and durable, suitable for electric drill, pneumatic drill, electric wrench, manual wrench, pneumatic screwdriver, electric screwdriver, etc. Steel hex connecting rod, chrome steel alloy vanadium, chrome plated, beautiful appearance, high hardness, strong and durable. Safety: Square with anti-breakage steel ball, the connection is tight and not easy to fall off, and safety is not firm. Material: 45 steel, chrome plated Material: CRV chrome vanadium steel alloy, chrome plated Appearance: Inner square transforms outer square (1/4"->3/8", 3/8"->1/4", 3/8"->1/2" , 1/2"->3/8") Have a great time shopping!