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, #45216, diameter (D): 3/8, cutting Height (B): 3/4, shank (D): 1/4, overall length (L): 2, flutes: 2, 45216 carbide Tipped straight plunge high production 3/8 dia x 3/4 x 1/4 inch Shank