Elora 34in square drive bi hexagon imperial sockets elora 640 professional quality sockets manufactured from chrome vanadium steel hardened tempered and chrome plated for corrosion protection chamfered end allows positive nut location and entry hole for driving accessory with locking pin some socket sizes have knurled band for extra hand grip sold loosemanufactured to din 3124iso 2725 and din 3120iso 1174 specifications elora 640 218 34 square drive bi hexagon socket