Includes triple square spline bit sockets Bits are made from S2 steel to meet or exceed torque specifications Sockets are made from heat treated chrome vanadium steel for strength & durability ATD carries a complete line of bit sockets available individually. Custom blow molded case included. These high quality triple square spline bit sockets are designed to be used with hand tools only. The bit socket warranty is voided if they are used with any type of impact tools. Set Includes: (10) Triple Square Spline Bit Sockets: ATD-232 - M4 1/4" Drive ATD-233 - M5 1/4" Drive ATD-234 - M6 1/4" Drive ATD-235 - M8 3/8" Drive ATD-236 - M9 3/8" Drive ATD-237 - M10 3/8" Drive ATD-238 - M12 3/8" Drive ATD-239 - M14 3/8" Drive Tamperproof ATD-241 - M16 1/2" Drive Tamperproof ATD-242 - M18 1/2" Drive Tamperproof