Internal Hex, Internal Torx, External Hex, TX, Hex
Imperial, Metric, Torx, AF, SAE
5/16 ", 5 mm, 9/16 ", 11/16 ", 1-1/2 "
1-1/2, 3/8, 2-1/2, 1/2, 1/4
12.5, 19.05, 6.35, 25.4, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide