Internal Hex, Internal Torx, External Hex, TX, Hex
Metric, AF, Torx, Imperial, SAE
9/32 ", 5/8 ", 5.5 mm, 5/16 ", 26 mm
6.35, 12.5, 25.4, 19.05, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Gun-metal, Oxidised, Black Phosphate, Black Oxide