3M Pro Grade Precision Ultra Flexible Sanding Sheets feature an innovative film backing so you can fold, roll or shape into any form you need to get the job done. The tough backing resists puncture, tear and creases, helping the sheet keep its original shape. Use wet or dry. 150 grit.Last 15X longer than conventional paper-backed sandpaperFor the best results, sand with the grain of the surface and work through a sequence of grits, from coarse to very fine, skipping no more than 1 grit between each sanding step (other grits not included)Great for interior and exterior projectsSheets are perforated for easy dispensingCan be used wet or dryCan be used on all surfaces4 1/2" x 7"