1/8X1/2X1/4X1-1/2. Produces super clean, smooth cuts especially in acrylic materials (Plexiglas® Lucite®) other plastics and wood. Bits are made according to strict tolerances from an exclusive carbide grade and polished to a mirror finish. Designed to eject chips up. Ideal for industrial applications and CNC machines. Right hand helix right hand cut. Feed rate is 18,000 RPM and 70 - 110" per minute.