The Forney 72753 4 Inch Knotted Wire Cup Brush is ideal for fast, heavy duty cleaning of large surfaces, removing weld scale, rust and burrs. Designed for use in high speed electric drills. Forney Industries is one of America's longest operating family-owned metal working product companies. Founded in 1932, Forney offers more than 5,000 products for the hardware, automotive, farm & ranch and do-it-yourself markets. For more information, visit www. forneyind.com. If you've got metal working questions, we've got answers. We're committed to your success regardless of location size or needs. Please contact our team at www. email@example.com. 4 inch (101.6mm) x .012 inch (.306mm) with 5/8 inch - 11 threaded arbor. Max 8,500 RPM. Claims for warranty must be made within 90 days of the date of purchase. Proof of purchase required. This warranty does not cover any product that has been subject to misuse, neglect, negligence or accident, or that has been used in any way contrary to the purpose intended.