Made of premium high-speed steel: These square hole drill bits are made of premium high-speed steel (HSS), offering excellent hardness, wear resistance, and lifespan. Ideal for efficient woodworking projects. Square Hole Mortising Design: Designed for clean, precise square holes in wood. Perfect for creating mortises for tenons, locks, hinges, and other joinery, enhancing the strength and aesthetics of furniture. Auger Drill and Chisel Combination: The inner anuger and outer square chisel work together to drill and chisel in one step, significantly improving efficiency compared to traditional methods. Ideal for DIY Furniture and Woodworking: Designed for DIY enthusiasts and professional woodworkers, suitable for making tables, cabinets, doors, frames, and other wooden furniture. Helps you achieve precise mortise and tenon joints for professional-grade results. Compatible with Bench Drills: Compatible with most bench drills and mortising machines that support square hole chisels. Please check shank diameter and machine compatibility before purchasing. Color: As Shown Material: High Speed Steel Package Contents: 4 * drill bits