Core box router bit with 1/4-inch heat-treated, hardened steel shank; double flute for quick cuts. Dynamically balanced up to 24,000 RPM to reduce vibration and kickback. Non-stick powder coat finish reduces friction and resin build-up to protect from corrosion. Premium quality Super Fine Grain Tungsten Carbide for an exceptionally smooth finish. Size: 5/8-inch diameter by 1/2-inch carbide height; 5/16-inch radius.
Nice tool, I used it on two hard maple cutting boards (12" x 21") and it did the job perfectly and is ready to use again . The package is great. Hard plastic but there is foam (2 layers on the bottom) to protect the bit. The hardest part is pulling it out as the package was stapled together, but in a carpentry shop that's not a problem. I would buy it again.