For high volume, high speed cutting in dense Natural woods and abrasive wood composites, use solid carbide Bits. Solid carbide dissipates heat more uniformly, extending tool life. Single flute bits cut faster, with better chip clearance. Two-flute bits cut more slowly, but leave a smooth finish. Maximum RPM 28, 000, #43720, diameter (D): 1/4, cutting height (B): 1, shank (D):, /4, overall length (L): 2, flutes: 1, 43720 Solid Carbide single flute straight, lunge 1/4 dia x 1 inch x 1/4 shank