Internal Hex, Internal Torx, External Hex, TX, Hex
Imperial, AF, Metric, Torx, SAE
5/16 ", 7/16 ", 7/32 ", 9/16 ", 11/16 "
1-1/2, 2-1/2, 3/8, 1/2, 3/4
25.4, 12.5, 9.53, 6.35, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphatized, Oxidised, Black Phosphate, Black Oxide