6" ExtensionMade of high quality steel (chrome-molybdenum)Extension is made with a friction ballTested to the highest specifications to deliver outstanding performance at the most competitive costLifetime warrantyThis 3/8" drive 6" extension is made with the friction ball. A spring loaded ball that line up with the socket retainer hole. Use caution when using this system because the socket is held in place only by spring pressure on the steel ball.