Made of silicon carbide for sanding and finishing of drywall joint compound. Can be used on wood, metal, plastic, and auto body filler. 4-3/8" x 11" sheets. 25 sheets per box. No. 4261: Grit: 150B Grit, Length: 11", Width: 4-3/8", Pkg Qty: 25, Package Type: Box No. 4262: Grit: 100B Grit, Length: 11", Width: 4-3/8", Pkg Qty: 25, Package Type: Box No. 4263: Grit: 80B Grit, Length: 11", Width: 4-3/8", Pkg Qty: 25, Package Type: Box