External Hex, Internal Hex, Internal Torx, Hex, TX
Imperial, Torx, Metric, AF, SAE
7/32 ", 9/32 ", 1 ", 5/16 ", 7/16 "
1-1/2, 1, 2-1/2, 1/2, 3/8
19.05, 38.1, 25.4, 9.53, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide