Extended shank design This router bit extension chuck features an extended shank with options of 6, 3.5 and 8 mm, enabling precise trimming, carving and shaping on electric routers and milling machines. High precision and durability Made from carbon steel, these collet heads deliver high precision and long lasting performance. They are built to withstand heavy use and provide consistent and accurate results. Versatile use and compatibility These collet heads are designed to convert trimming machines for a range of woodworking applications. They are compatible with different machine sizes and support bore diameters of 6 mm, 3.5 mm or 8 mm. Practical and reliable Constructed to meet the demands of professional woodworking projects, these carbon steel collet heads are practical and reliable tools to help you achieve your woodworking results. Use scenarios - Edge trimming and profile shaping on panels with trim routers for precise finishes - Detailed carving and decorative work requiring stable and accurate control - Cabinetry and furniture finishing with small profile trims and inlays