Whiteside RD5200 Downcut Spiral 1/2" Shank 1/2" Cut Dia. 2" Cut Length1 2"SH, 1 2"CD, 2"CL Spiral bits provide a shear cutting edge that leaves a smoother cut than standard router bits. The down cut spiral design provides the best top surface edges, ejecting chips away from the router when routing through material. This design also decreases the tendency to lift thin small work pieces during CNC routing. Materials: Natural woods, composites, hard plastics, thin aluminum Recommended RPM: 16,000 18,000 (max 24,000)