Internal Hex, External Hex, Internal Torx, Hex, TX
Imperial, Metric, Torx, AF, SAE
19 mm, 7/16 ", 5/8 ", 9 mm, 11/16 "
3/4, 1, 2-1/2, 1-1/2, 1/2
19.05, 25.4, 6.35, 9.53, 38.1
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide