46477 Solid Carbide Down-Cut Ball Nose Spiral 1/2 Dia x 1-1/4 x 1/2 Inch Shank Router Bit
Astra Coated* 1/16" Down Cut CNC Router Bit - BitsBits.com
Whiteside Router Bits RD2100 Standard Spiral Bit with Down Cut Solid Carbide 1/4-Inch Cutting Diameter and 1-Inch Cutting Length - Down Spiral Router Bits - Amazon.com
Spiral Router Bits vs. Straight Router Bits
46476 Solid Carbide Down-Cut Ball Nose Spiral 1/4 Dia x 1 Inch x 1/4 Shank Router Bit