Bulk Packaged 6pc 120 Grit 1/2 x 1/2 inch Sanding Bands. Compare to Dremel 432. Use with 1/2 x 1/2 inch Sanding Mandrel, Not included. For use with Dremel Rotary Tools. 35,000 RPM is recommended for brass, steel and aluminum. 10-35,000 RMP is suggested for ceramic, hard or soft wood, stone and shell. The RMPs recommended for plastic are 10-20,000; for copper 25-35,000.