External Hex, Internal Hex, Internal Torx, TX, Hex
Imperial, Metric, AF, Torx, SAE
5/8 ", 9/16 ", 11/16 ", 23 mm, 1-1/2 "
6.35, 25.4, 19.05, 38.1, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Phosphated, Oxidised, Black Oxide, Black Phosphate