The Britool 1/2in Drive 12-point long sockets (metric) are crafted from chrome vanadium steel with a high chrome finish. The OGV profile allows tightening torque to be applied to the sides rather than to the angles of the nut. This product is for manual use only. ISO 2725-1, DIN 3124, ISO-1174-1, ISO-1711-1, ISO 691.