- Quality materials: This hard alloy rotary file kit is made of tungsten carbide steel, sharp and durable for high efficiency, smooth operation, long life, and high precision. - Different shapes and performance: The double-cut type features rows of cutting teeth that cut along two intersecting directions, enabling quick material removal and a rougher finish. Different shapes are included to meet a range of tasks. - Easy to use: 8-piece hard alloy rotary file kit with a 1/4 inch handle, including SA and SF files. Suitable for all skill levels and ideal for woodworking, cleaning, and frequent welding or general work. - Compatibility and scope: Hard alloy files fit most small rotary tools and mold grinders, and can be used with high-speed electric grinders or pneumatic tools. - Practical use scenarios: - Deburring weld seams and smoothing edges on metal parts and castings. - Refining plastic molds, dies, and small components. - Smoothing hard-to-reach edges in hobby projects or model-making work.