The perfect Keyhole does exist! Clean cuts, every time for the CNC, handheld router, or router table!
 
Large Cut Diameter: 0.375" (3/8")
Small Diameter: 0.25" (1/4")
Cut Length: 0.375" (3/8")
Shank Diameter: 0.25" (1/4")
 
 
All HCT bits are designed for cutting wood, non-ferrous metal (aluminum/brass/soft metals), and synthetic/plastic-based materials like epoxy and sheet plastics. Bit performance varies with machine type, feeds/speeds set, and the stock material.