Internal Hex, Internal Torx, External Hex, TX, Hex
AF, Imperial, Torx, SAE, Metric
5.5 mm, 11/16 ", 5/8 ", 3/16 ", 7 mm
1-1/2, 1, 3/4, 2-1/2, 1/2
38.1, 6.35, 25.4, 9.53, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide