The two most common joint profiles you will see are concave and flat. This tool will do either. Bon was thinking efficiency when they made this tool. The downside? It's only available in 3 joint sizes.
Fun Facts:
- Features a convex blade on one side for tooling concave joints
- Flat blade on opposite side for tooling flat joints
- Made from abrasion resistant high carbon steel
- Lightweight
- Available in 3 sizes 1/2", 5/8" & 3/4"