Tool-Flo 1271401 Helical Flute Thread Mills; Material: Carbide ; Thread Size (Inch): 9/16-12 ; Thread Type: Internal ; Shank Diameter (Decimal Inch): 0.5000 ; Cutting Diameter (Decimal Inch): 0.4130 ; Length Of Cut (Decimal Inch - 4 Decimals): 1.2400