Pre-cut sheets are uniform and even in size! Lightweight but strong and rigid to resist denting and crushing. Resilient polystyrene core bounces back after cutting to keep the board uniform edge to edge. The smooth surface satisfies a wide range of media including markers and paint. Perfect for crafts, school projects, framing and mounting. Art Board Type: Flat Display & Presentation Board; Material(s): Polystyrene Core; Color(s): White; Board Size Open (W x H): 18" x 24".