6mm Straight Cutter Handle-Knife handle diameter: 6mm. Includes 7 different straight router bits that meet the basic needs of woodworking slotting. (Please check the size and suitability before purchasing)Low Speed Use-The router bit head is made of YG8 hard alloy and the handle is made of 45# carbon steel. These alloy wood router bits are more suitable for roughing wood products at low speeds.Heat-resistant coating-The green heat-resistant coating of the router bit set prevents the accumulation of sawdust, resin and asphalt and improves your work efficiency.Composite cutting-Router bits suitable for making grooves and all kinds of straight cutting work, cutting all composite materials, wood, medium density fiberboard, particle board, compact plywood.Woodworking enthusiasts' choice-Heavy duty router bits for cutting and CNC. Suitable for trimming and grooving to complete wood projects. For woodworkers and enthusiasts, this is a great choice.