Internal Hex, Internal Torx, External Hex, TX, Hex
AF, Torx, Imperial, SAE, Metric
7/16 ", 9/16 ", 3/16 ", 5.5 mm, 11/16 "
19.05, 9.53, 25.4, 38.1, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Phosphate, Black Oxide