Internal Hex, External Hex, TX, Hex, External Torx
AF, Metric, Imperial, Torx, SAE
5.5 mm, 9 mm, 5/16 ", 1-1/2 ", 11/16 "
2-1/2, 1-1/2, 1/2, 3/4, 3/8
38.1, 25.4, 9.53, 6.35, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide