Amana 57307 Solid Carbide CNC Spiral ‘O’ Flute, Aluminum Cutting 3mm Dia x 12mm x 6mm Shank x 50mm Long Down-Cut Router Bit Amana 57307 Solid Carbide CNC Spiral ‘O’ Flute, Aluminum Cutting 3mm Dia x 12mm x 6mm Shank x 50mm Long Down-Cut Router Bit