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