3M Trizact Glass Restoration Disc (5in Coarse) 3m Trizact 35 micron 5 inch Diameter with center hole for option water feed machines. Individual. Pressure sensitive adhesive (PSA) backing. Attached to any 5 inch diameter PSA type backing pad. Great for removing heavy/deep scratches in glass surfaces and many other surfaces. 3m 20 micron, 10 micron, 5 micron and polishing disc must follow this disc in this order for final clarity on glass surfaces. 5 inch Trizact material works great for repairing larger damage on glass surfaces.