3M™ ProPak™ Aluminum Oxide Sandpaper for paint and rust removal. Use on paint, wood and metal. Features a flexible "A" weight backing for contour sanding and fine finishing before coating. 3M abrasives are the choice of professionals for sanding a wide variety of materials and surfaces. This aluminum oxide abrasive is an extremely tough and durable synthetic material. The resin coating increases the life and cut of the sandpaper and outlasts ordinary gluebond paper.