The Forney 72401 6-inch type 1 bench grinding wheel is a vitrified bond, aluminum Oxide wheel. Designed for most stationary bench grinders. For general grinding and sharpening applications on mild steel. Not for carbide applications. The 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 and ranch and Do-It-Yourself markets. 6-Inch (152.4 mm) by 3/4-Inch (19.05 mm) with 1-inch (25.4 mm) Arbor. 36 grit. Max 4, 100 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.