External Hex, External Torx, Internal Hex, TX, Hex
AF, Metric, Torx, Imperial, SAE
5/16 ", 5/8 ", 5 mm, 5.5 mm, 11/16 "
1, 1-1/2, 2-1/2, 1/2, 3/8
25.4, 9.53, 19.05, 38.1, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide