SATC sanding sponges are designed for sanding wood, paint, metal, plastic or drywall. This sponge is made with special Black Fused Alumina Abrasives, and High Density Sponge which features durable and flexible. The block shape makes it easy to hold and sands flat, contoured, or irregular surfaces. Sanding is an integral step in preparing a surface to receive a coating. For the best sanding results, sand with the grain of the surface and work through a sequence of grits, from coarse to very fine, skipping no more than one grit between each sanding step. SATC 6PCS Sanding Blocks Assortment includes grit 60/80/100/120/180/220, from Coarse to Extra Fine. Specifications Color: Greyish Black Abrasive: Aluminum Oxide, Black Fused Alumina Matrix: High Density Sponge Bonding: Resin Width: 2-3/4 in Length: 4 in Thickness: 1 in Grit and Grade: 60 Coarse / 80 Medium / 100 Medium / 120 Fine / 180 Fine / 220 Extra Fine Package Included 12PCS Assort Grit Sanding Sponges Product Net Content Quantity 2 x 60 Grit Sanding Sponge 2 x 80 Grit Sanding Sponge 2 x 100 Grit Sanding Sponge 2 x 120 Grit Sanding Sponge 2 x 180 Grit Sanding Sponge 2 x 220 Grit Sanding Sponge Note: The sanding sponges are disposed of after several uses, or when there is no longer texture on the block