Internal Hex, Internal Torx, External Hex, TX, Hex
Imperial, AF, Torx, SAE, Metric
7/32 ", 9/32 ", 5.5 mm, 5/16 ", 11/16 "
1, 1-1/2, 2-1/2, 3/8, 1/2
19.05, 38.1, 25.4, 6.35, 9.53
Special Steel, Molybdenum Steel, Alloy Steel, Steel, Chrome Molybdenum Alloy Steel
Phosphatized, Gun-metal, Oxidised, Black Phosphate, Black Oxide