TruePower Triple Square Spline Bit Socket Set, Metric, 10-Piece Steel Imported Includes: (10) Triple Square Spline Bit Sockets: M4 1/4" Drive (ATD-232); M5 1/4" Drive (ATD-233); M6 1/4" Drive (ATD-234); M8 3/8" Drive (ATD-235); M9 3/8" Drive (ATD-236); M10 3/8" Drive (ATD-237); M12 3/8" Drive (ATD-238); M14 3/8" Drive Tamperproof (ATD-239); M16 1/2" Drive Tamperproof (ATD-241); M18 1/2" Drive Tamperproof (ATD-242) Bits are made from Drop-forged, heat-treated S2 steel that will last longer than any others in its class Sockets are made from heat treated chrome vanadium steel for strength and durability Includes: Storage Case