Internal Hex, External Hex, Internal Torx, Hex, TX
AF, Metric, Torx, Imperial, SAE
15 mm, 7/16 ", 5/8 ", 23 mm, 11/16 "
1-1/2, 1/4, 3/8, 2-1/2, 1/2
25.4, 6.35, 19.05, 38.1, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide