Bisco Tool Supply sells Grinding Discs. These USA Abrasives size 4-1/2"x1/4"x5/8-11 are Flexovit Free Grind Depressed Center Grinding Disc for Stainless Steel and Alloy Metals. Provides a Smooth and Fast Grind. Flexovit Industrial Abrasive Discs. Made in the USA by Flexovit High Quality Industrial Abrasive Products. Sold in box quantities of 10.