Description: High-grade welding, stable quality, high efficiency. Using for kinds of woodworking. Totally enclosed and lubricated . Carbide Tipped - Micro grain grade provides increased strength and utmost resistance. Made of high quality metarial, durable and stable. Specification: Color: Silver Material: Carbide Shank diameter: 1/4" (6.35mm) Bearing diameter: Approx. 1/4" (6.35mm) & 5/16" (7.96mm) & 3/8" (9.52mm) & 1/2" (12.7mm) Blade length: Approx. 20mm (0.79") & 20mm (0.79") & 20mm (0.79") & 25mm (0.98") Total length: Approx. 60mm (2.36") & Approx. 60mm (2.36") & 60mm (2.36") & 65mm (2.56") Package Includes: 1 Set of Flush Trim Router Bit (4 Pack? Note: The color may be different for different display, pls understand Pls allow 1-2mm error due to hand test Pls check the pictures for more details, thank you