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