Webb HPF Hand Pad Sanding Sponge Fine 3-3/4-Inch x 4-3/4-Inch x 1/2-Inch Dimensions: 3 3/4" x 4 3/4" x 1/2" 2-sided fine (100) grit coating: Brown aluminum oxide Features Clog Resistant Technology (CRT) Backing material: PU Blue foam (polyurethane), solvent free Extra soft foam for maximum adaptability Firm, yet flexible foam with durable grit on all 4 sides easily adapts to all surfaces, edges and profiles Use wet or dry Features clog-resistant technology