Gator waterproof sanding sheets are designed for applications where wet sanding is required. The paper backing is specially treated to maintain it's strength and shape even after being soaked in water for an extended period of time. The sharp, fast cutting silicon carbide grain works well on metal surfaces and between coats of paint, primers and sealers. For wet sanding primers, base coats, and top coatsThe premium backing allows the sandpaper to be submerged in water for an extended period of time without any adverse effects on the quality of the sanding sheetFor hand or machine sandingCut to fit 1/2, 1/3, or 1/4 sheet clamp-on sandersFlexible paper backing for easier hand sanding