External Torx, Internal Torx, External Hex, Hex, TX
Imperial, AF, Metric, Torx, SAE
5/16 ", 7/8 ", 3/16 ", 5.5 mm, 15 mm
9.53, 12.5, 6.35, 25.4, 38.1
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Phosphate, Black Oxide