Chrome Vanadium Steel CR-V Reducer Adapters Set for Socket Wrench? Materiall: chrome vanadium steel Designed for impact use, locks onto socket and drive tang 1/2" to 3/8" - 12.5mm square hole to 9.5mm square head; 3/8" to 1/4" - 9.5mm hole to 6.3mm head 3/8" to 1/2" - 9.5mm square hole to 12.5mm square head; 1/4" to 3/8" - 6.3mm hole to 9.5mm head Weight: 4.73 oz (134 g)