Use a Two-Flute bit where fine finish is paramount. Two flutes balance the bit, eliminating vibration that degrades the cut finish. Two cuts per revolution Yield a smooth surface, but feed rate is slightly reduced, #45217, diameter (D): 13/64, cutting height (B): 3/4, shank (D): 1 /4, overall length (L): 2, flutes: 2, 45217 carbide Tipped straight plunge high production 13/64 dia x 3/4 x 1/4 inch shank