Extra long 4" shank Bits are made from S2 steel to meet or exceed torque specifications Sockets are made from heat treated chrome vanadium steel for strength & durability Custom blow molded case included. ATD carries a complete line of bit sockets available individually. 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) Extra Long Triple Square Spline Bit Sockets: M4 1/4" Drive - ATD-243 M5 1/4" Drive - ATD-244 M6 1/4" Drive - ATD-245 M8 3/8" Drive - ATD-246 M9 3/8" Drive - ATD-247 M10 3/8" Drive - ATD-248 M12 3/8" Drive - ATD-249 M14 3/8" Drive Tamper-Resistant - ATD-252 M16 1/2" Drive Tamper-Resistant - ATD-253 M18 1/2" Drive Tamper-Resistant - ATD-254