Trusted by professionals, the Capri Tools high performance sockets are what you need for the job at hand Premium Chrome Molybdenum steel tempered with our proprietary heat treatment process to withstand more torque from power tools Expertly coated with manganese phosphate, the preferred coating in military and aerospace, which offers superior protection and corrosion resistance compared to black oxide coating on other impact sockets 6-point WaveDrive design grips fasteners more tightly than traditional design, preventing fastener rounding and giving you more leverage Single shallow length, 3/8 in. drive, 18 mm size socket