Industrial quality aluminum cutting router bits are made by Amana Tool, the leading manufacturers of cutting tools. Aluminum cutting router bits by Amana feature outstanding tool longevity, a tendency to stay sharper, mirror like carbide finish, excellent carbide brazing, a broad selection of sizes and most importantly quality of cut. Amana Tool 51508-Z SC Spiral 'O' Single Flute, Aluminum Cutting 3/16 D x 1/2 CH x 1/4 SHK x 2 Inch Long Down-Cut ZrN Coated Router Bit with Mirror Finish uses the highest quality sub-micrograin carbide, have a special proprietary edge processing system and feature 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. Excellent for: ALPOLIC Copper Composite Material (CCM), Alucobond, Aluminum, Aluminum 5052, Aluminum 6061, Aluminum Alloys (Al-Alloy), Aluminum Composite Materials (ACM), Aluminum Composite Panel (ACP), Alupanel, Brass, Copper, Dibond, Durabond, e-panel, Etalbond, Fomex with Aluminum Face, Gold, Non-Ferrous Metals, Plastic, Silver, Solid Surface, Titanium Composite Material (TCM), Wood. SPECIFICATIONS: Direction: Down-Cut; (D) Diameter: 3/16; (B) Cutting Height: 1/2; (d) Shank: 1/4; Overall Length (L): 2; Flutes: 1.