6mm shank keyhole cutter set, cutter diameters 5/16", 3/8", 1/2". C3 micrograin tungsten carbide inserts, high quality alloy steel body .Built-up and heat resistant Teflon coating. Works with solid wood, particleboard, MDF, plywood, etc. Creates a very nice clean cut with minimal touch up sanding. These T-slot milling cutters for hex bolts. Designed for handheld and tabletop routers, not for power drills and drills. Product Description Specifications: Commodity: 6mm Shank Milling Set Material: 45 Carbide Steel Carbide Tip: YG8 Handhold Diameter: 6mm Tip Diameters: 5/16", 3/8" and 1/2" Body: Solid Hardened Steel Blade: Industrial Grade Micrograin Carbide Package Included: 1 xRouter Bit 5/16 Inch Tool Diameter 1 xRouter Bit 3 /8" Tool Diameter 1 xRouter Bit 1/2" Tool Diameter Safety Instructions: 1. This item is for industrial cutting/engraving only. 2. When not in use, put in a plastic box. 3. The scope of use is suitable for hardwood, particleboard, MDF, plywood, acrylic; avoid cutting ferrous metals and non-wood materials, iron, etc. 4. Please wear protective measures.