Bosch Impact Control Socket Set is highly robust when screw-driving hex screws with impact drivers and wrenches. S2 Modified Steel and an optimised heat-treatment process provide the socket with extra-tough endurance for high performance. This product is intended for screw-driving heavy-duty applications such as plant installations or in heavy industrial work. The set includes 9 sockets with a 3/8" drive and a length of 63mm. The widths across flat are 7; 8; 10; 12; 13; 15; 16; 17; and 19 mm.