External Hex, Internal Hex, Internal Torx, TX, Hex
Imperial, Metric, AF, Torx, SAE
5/16 ", 7/16 ", 9/16 ", 3/16 ", 5/8 "
1-1/2, 1/4, 3/8, 1/2, 3/4
12.5, 25.4, 6.35, 9.53, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide