Internal Hex, Internal Torx, External Hex, Hex, TX
Imperial, Torx, AF, SAE, Metric
5/16 ", 7/8 ", 12 mm, 28 mm, 1-1/2 "
1, 3/4, 1-1/2, 2-1/2, 1/2
25.4, 9.53, 6.35, 38.1, 12.5
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide