Draper expert 50mm 12 square drive wobble extension bar draper expert 13923 expert quality manufactured from chrome vanadium steel hardened tempered chrome plated and polished for corrosion protection enables sockets to be driven at up to 15176 to the vertical spring loaded ball bearing for secure socket holding overall lengths can vary in production display packedmanufactured and tested generally in accordance with din3122 and iso3315 specifications draper expert 13923 50mm 12