Internal Hex, Internal Torx, External Hex, Hex, TX
AF, Imperial, Torx, Metric, SAE
5/16 ", 7/16 ", 7/32 ", 9/16 ", 9 mm
3/4, 1, 1-1/2, 2-1/2, 1/2
38.1, 6.35, 19.05, 9.53, 12.5
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Gun-metal, Oxidised, Black Oxide, Black Phosphate