United abrasives – sait 50196 9s fiber disc 7″ x 7/8″ 36 grit ceramic high performance, ceramic grain with grinding aid. Closed coat, grinding aids for reduced heat and decreased loading. Excels on heat sensitive materials. Exceptional performance and value. Resin over resin construction for a strong bond that is resistant to heat and moisture. Vulcanized fiber backing for heavy duty sanding.