Premium CR-V: This 18-Piece Drive Tool Accessory Set made from Heavy-duty Chrome-Vanadium steel alloy with a corrosion-resistant black phosphate finish, providing the durability for a hard use Complete Set: This set includes: 1/4"Dr Extension Bar: 3" & 6"; 3/8"Dr Extension Bar: 3"& 6"&10"; 1/2"Dr Extension Bar: 3"& 6"&10"; Impact Socket Adapter: 1/4"F * 3/8"M, 3/8"F * 1/4"M, 3/8"F * 1/2"M, 1/2"F * 3/8"M; Impact Univeral Joint: 1/4"Dr, 3/8"Dr, 1/2"Dr; Impact Coupler: 1/4"Hex * 1/4"Dr, 1/4"Hex * 3/8"Dr, 5/16"Hex * 1/2"Dr Versatile: This high quality impact socket accessory set includes the sizes and tools you'll need for almost any project. Socket extensions for reaching tight space, universal joints for changing angles and getting narrow area, socket adapters allow using different drive size sockets, coupler can be used to convert different screwdrivers for installation and removal of bolts Easy Identification: All drive tools are marked with size to facilitate identification and get appropriate size accessories, saving time and effort Convenient Storage: The professional socket accessory kit comes with a heavy duty blow molded storage case for easy transportation, safe storage, and quick organization WORKPRO 18-Piece Drive Tool Accessory Set The WORKPRO 18-Piece Drive Tool Accessory Set, which is made from drop forged and heat-treated chrome vanadium steel (50BV30) with black phosphate finish, providing the durability for a hard use. High-contrast size marking is permanently laser etched and easy to read, even in low light. Service Stay Organized All WORKPRO tools meet or exceed ANSI performance standards. Includes a heavy duty blow molded case to keep your sockets free from dirt and grime when not in use. Extensions Universal Joints Couplers Adapters Spring loaded detent ball on extension ends provide secure fit into sockets, delivering support when used with high torque impact drivers. The impact universal joints allow for a full 360° rotation to access hard-to-reach fasteners. The coupler is made of heat-treated chrome vanadium steel with corrosion-resistant black phosphate finish. Used with different bits meet your needs. The Adapters can convert your impacts to different size sockets.