ZHIDA Torx Impact Screw Bit Set T3,T4,T5,T6,T8,T10,T15,T20,T25,T27,T30,T40 1 Set Made in alloy steel hardness HRC can be 62 Precision CNC machine made, match standard TORX screw perfect. (in the market some screw is not standard, some screw coating is very thick, standard bits hard to match very well, custom screw bits available. Pretty laser marking.