Internal Hex, Internal Torx, External Hex, TX, Hex
AF, Imperial, Torx, SAE, Metric
5/16 ", 16 mm, 14 mm, 11/16 ", 36 mm
25.4, 12.5, 6.35, 19.05, 38.1
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Phosphate, Black Oxide