Featuring waterproof paper backing, 3M Wetordry Sandpaper has been a trusted resource in automotive repair, it delivers true versatility even if you're wet sanding one area and dry sanding the next, The 3M Wetordry Sandpaper lets you keep moving without having to switch sandpaper and it delivers a 10% smoother finish than other conventional sandpaper Features silicon carbide abrasive, a synthetic mineral that is very sharp and commonly used for low-pressure applications such as paint prep, smoothing of clear coats and as an alternative to compounding Each sheet is durably resin bonded onto a waterproof paper that helps conform to metal, plastic body filler or fiberglass sanding surfaces, whether by hand or machine This range of sandpaper for wet or dry sanding is excellent for use in the Fill, Paint and Finish stages of the 3M Body Repair System