Britool expert by facom E117353 1/4" socket - Hex - Metric 13mm - ISO 2725-1 - DIN 3124 - ISO 1174-1 - ISO 1711-1 - ISO 691 - Chrome vanadium steel. - OGV Profile: tightening torque applied to the sides rather than to the angles of the nut. - High chrome finish. - For manual use. The 1/4 inch Drive sockets have a Hex socket (6 point) end and are made from chrome vanadium steel with a high chrome finish. The OGV Profile allows for tightening torque to be applied to the sides rather than to the angles of the nut. These sockets are for manual use only. ISO 2725-1, DIN 3124, ISO1174-1, ISO691, ISO1771-1.