Grinding Wheel, "Forney Flex" 36 Grit Metal, Type 27, Depressed Center, 4" X 1/8" X 5/8" Arbor AC36R-BF. Aluminum oxide metal grinding wheel. Forney Flex Discs will become 'flexible' as they warm up. Innovative concept combines advantages of depressed center grinding wheels & resin fiber discs. As heat builds up during use, the double reinforced wheel becomes flexible and pliable, conforming to the surface being ground. The wheel flex during grinding process creates a large surface contact area for easy finish quality blending operations and reduced risk of gouging material. Great for auto body work. Designed for metal grinding, metal abrasion, metal fabrication and general repair work. Used on ferrous materials. For use on right angle grinders. Wheel Size: 4