The Forney 71647 4-1/2-Inch Blue Zirconium 24 Grit Type 1 Steel Sanding Discs are high quality disc that cuts faster and lasts longer than most other discs on the market. High performance for grinding, deburring, polishing metals, welds and stainless steel. Fast stock removal. Extremely long life. Cool cutting action. 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. If you've got metal working questions, we've got answers. We're committed to your success regardless of location size or needs. 4 1/2 inch (114.3 mm) with 7/8 inch (22.23 mm) arbor size, 24 Grit. Made from 100% zirconia grain, 3-pack. 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.