External Hex, Internal Hex, Internal Torx, TX, Hex
AF, Metric, Imperial, Torx, SAE
5/16 ", 7/16 ", 3/16 ", 8 mm, 9/16 "
3/8, 1/4, 3/4, 1-1/2, 2-1/2
6.35, 12.5, 19.05, 38.1, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Phosphatized, Oxidised, Black Oxide, Black Phosphate