Amana collet reduction sleeves 1/2" to 3/8". These reduction bushings are precisely machined from high quality steel to limit the chance of run-out. Reduction bushings are not a long term solution for your CNC router. To get the most out of your CNC router, a proper sized collet is strongly recommended.
Diameter: 1/2
Shank: 3/8
Overall Length: 1-3/16