Internal Hex, External Torx, External Hex, Hex, TX
AF, Imperial, Torx, SAE, Metric
15/16 ", 5/16 ", 5 mm, 11/16 ", 1-1/2 "
3/8, 1/4, 1-1/2, 2-1/2, 1/2
38.1, 6.35, 9.53, 25.4, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide