3M(TM) Cloth Belt 577F, 1 1/4 in x 96 in P40 YF weight Filmlok, 50 per case An alumina zirconia belt constructed on a YF weight, water resistant polyester cloth backing. Resin bonded for heat resistance. Features grinding aid for cooler grinding. Can be run wet or dry. Grade: P40. Primary market: metalworking.