Impact 6-point hex sockets specifically forged for use on powered impact tools. Precision cold-forged hardened and tempered chrome vanadium steel. Clear laser-etched sizes and industrial phosphate-coated for tough corrosion resistance. Thick walls provide strength and durability for repetitive high torques. Side wall hole for ball or pin locking to the tool. Contents: 10 11 12 13 14 15 17 19 21 and 22mm.