7 inch x 7/8 inch center hole black Silicon Carbide heavy duty "E" weight paper edger sanding discs. Slotted with 4 slots on each disc. Slotted discs bolt on to appropriate back up pad attached to an orbital or DA disc sander. Used for sanding on hardwood and softwood flooring as well as natural stone, plastic, fiberglass and concrete. High quality German industrial abrasives factory direct.