Internal Hex, Internal Torx, External Hex, Hex, TX
AF, Torx, Metric, Imperial, SAE
7/16 ", 15/16 ", 5.5 mm, 23 mm, 1-1/2 "
38.1, 6.35, 25.4, 9.53, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Gun-metal, Oxidised, Black Phosphate, Black Oxide