Multiple Specifications: 3 pieces of 8 mm shank 45-degree lock miter router bits, including 1-3/8 inch, 1-1/2 inch, and 2 inch cutting diameters, suitable for materials of different thicknesses. Made of hard alloy steel with high hardness; the heat-treated blade is sharp and smooth. The coated surface provides rust resistance and extended service life. Universal woodworking tool: 45-degree lock miter router bit set designed to join boards at 90 degrees, allowing easy assembly by routing one board vertically and the mating board horizontally. Suitable for use on MDF, solid wood, particle board, plywood, wooden door frames, windows, cabinets, boxes, and similar applications. Compatible with CNC routers, automatic routers, handheld routers, and table-mounted portable routers.