External Hex, Internal Torx, Internal Hex, TX, Hex
Imperial, Metric, AF, Torx, SAE
9/16 ", 5.5 mm, 16 mm, 5/16 ", 11/16 "
1/4, 3/4, 2-1/2, 1-1/2, 1
9.53, 12.5, 25.4, 19.05, 6.35
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide