Important Safety Note: To prevent bending and potential injury, the burrs maintain continuous contact with the workpiece during operation. Avoid exceeding 6000rpm when idling and 11000rpm when in contact with the workpiece. Designed for accessibility, these burrs are ideal for intricate areas. For safety, always wear protective gear including ear, eye, and face protection, and gloves. Handle the tool with a firm, controlled grip using both hands to minimize wobble. Ideal for detailed work on cast iron, steel, and aluminum materials, these long shank carbide burrs are perfect for deburring, smoothing, grinding, and porting in automotive applications like cylinder heads and intake/exhaust manifolds. Engineered for durability and aggressive performance, these and well-balanced burrs come with a five-year, hassle-free replacement , ensuring long-term reliability and customer satisfaction. Colour:silver Material:Tungsten steel Due to different batches, there may be differences in product appearance and printed text, which not affect use Package Contents: 4 * Long Shaft Tungsten Carbide Burrs Set Kit Bits Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.