Internal Hex, External Hex, Internal Torx, TX, Hex
Imperial, Torx, AF, Metric, SAE
7/16 ", 13/16 ", 13 mm, 18 mm, 11/16 "
38.1, 25.4, 6.35, 12.5, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide