Internal Hex, External Hex, Internal Torx, TX, Hex
Imperial, Torx, AF, Metric, SAE
7/8 ", 5 mm, 3/16 ", 5/16 ", 9/16 "
1-1/2, 3/4, 1, 2-1/2, 1/2
38.1, 25.4, 9.53, 6.35, 19.05
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide