MA Ford 61B050004, 1/2 HSS UniFlute Countersink,100 Deg, Blaze Coated, Diameter: 1/2, Shank Diameter: 1/4, Overall Length: 2, Included Angle Degree: 100, Base Material: HSS, Number of Flutes: 1, MPN: 61B050004, PKG QTY: 1 PC, Description: MA Ford Series 61 HSS Uniflute Countersink. The original single flute countersink designed for general purpose countersinking, chamfering or deburring.