Internal Hex, Internal Torx, External Hex, TX, Hex
AF, Metric, Torx, Imperial, SAE
5/16 ", 7/32 ", 7/16 ", 11/16 ", 3/8 "
1/2, 1/4, 3/8, 2-1/2, 3/4
6.35, 9.53, 25.4, 38.1, 12.5
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide