[Material] - The wood router bit kit is made of hot-hardened carbide cutting edges and forged tool holders, high strength, high hardness, good wear resistance and strong impact resistance. [Various Sizes] - Arbor Diameter: 8mm; Cutting Length: 40mm/ 50mm/ 63mm/ 76mm; Total Length: 72mm/ 84mm/ 97mm/ 109mm; Number of Grooving Cutter: 4. [Precise] - The high-quality router bit ensures professional and ultra-precise machining on wood. [Clean Cutting] - The router bit has clean cutting, stable rotation, fast operating speed, the cutting material has no burrs, and the use effect is perfect. [Suitable for] - The router bit can be used to groove a wide range of materials, including solid wood, MDF, particle board, plywood. Note: The data are all measured manually, please allow 1-3cm error due to differences in light and display, there may be some color differences, please refer to the actual item received.