Internal Hex, Internal Torx, External Hex, TX, Hex
Imperial, Torx, AF, Metric, SAE
3/16 ", 11 mm, 5/16 ", 5/8 ", 3/4 "
1, 1-1/2, 3/8, 2-1/2, 1/2
9.53, 38.1, 25.4, 6.35, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Oxide, Black Phosphate