MA Ford 61B100004, 1 HSS UniFlute Countersink,100 Deg, Blaze Coated, Diameter: 1, Shank Diameter: 1/2, Overall Length: 2-3/4, Included Angle Degree: 100, Base Material: HSS, Number of Flutes: 1, MPN: 61B100004, 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.