The Powerbuilt 3/4 Inch Drive 4 Inch Extension Bar is the perfect socket extension to span the gap to tucked away fasteners. It’s made from high-quality Chrome Vanadium steel with a mirror-polished chrome-plated finish for durability and long tool life. Extensions are perfect solution tools for when accessing hard-to-reach places like when working in and around engines, under the chassis, or any other jobs that require a longer reach in a tight space. No need to worry about dropping sockets into narrow spaces the Powerbuilt extensions also feature spring-loaded detent balls to help lock into and secure the sockets for worry-free retention. Dependable Powerbuilt socket extension bars meet or exceed ANSI standards and have a lifetime warranty.