Webb Abrasives 310039 Detail Pad Sanding Sponges, Fine Grit (24 Pack), 4 1/4" X 5 1/4" X 1/4" Dimensions: 4 1/4"x 5 1/4"x 1/4" 1-Sided fine (100) grit coating: brown aluminum oxide and silicone carbide Features clog resistant technology (crt) Backing material: eva blue foam (ethyl vinyl acetate), pu blue foam Foam hardness: soft, for optimum adaptation