Internal Hex, Internal Torx, External Hex, Hex, TX
Imperial, AF, Metric, Torx, SAE
9/16 ", 5.5 mm, 11 mm, 7/16 ", 1-1/2 "
6.35, 38.1, 25.4, 9.53, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphated, Gun-metal, Oxidised, Black Phosphate, Black Oxide