Internal Hex, Internal Torx, External Hex, TX, Hex
Metric, Torx, AF, Imperial, SAE
7/32 ", 5/16 ", 17 mm, 7/16 ", 11/16 "
1, 2-1/2, 1-1/2, 1/2, 3/8
19.05, 25.4, 6.35, 9.53, 38.1
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Gun-metal, Phosphated, Oxidised, Black Phosphate, Black Oxide