To be used only on CNC machines and routers with automatic feeding. Using the highest quality sub-micrograin carbide These bits have a special proprietary edge processing system featuring a super high polished cutting edge with a unique “mirror finish” Resulting In clean cuts, less chance for chip re-welding, a superior surface finish and a longer tool life. Right hand helix right hand cut., #51489, direction Up-cut, (D) diameter 1/2, (b) Cutting height 1-5/8, (D) shank 1/2, overall length (L) 3-1/2, flutes 1, 51489 Solid Carbide CNC spiral 'o' Single flute, aluminum Cutting 1/2 dia x 1-5/8 x 1/2 shank x 3-1/2 inch long Up-cut router bit