Art Advantage Hardboard Paintng Panel 18 in. x 18 in. - Inexpensive alternative to canvas panels. .13 in. warp resistant, acid free, high-density fiberboard, HDF. Can be painted on directly. Also accepts all acrylic gesso and oil priming grounds. Could be used as a mixing palette or as a base when taping down watercolor papers. Measures approximately 18 in. x 18 in. x .13 in.