External Hex, Internal Hex, Internal Torx, TX, Hex
Imperial, Torx, AF, SAE, Metric
5/8 ", 9/16 ", 5/16 ", 7/16 ", 34 mm
3/8, 1/4, 3/4, 2-1/2, 1/2
25.4, 12.5, 6.35, 9.53, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Oxide, Black Phosphate