Gessoed Boards & Masonite Blanks
Gessoed Boards are masonite hard boards preprimed to accept most paints.
Masonite is a hardboard made of compressed wood fibers. Artists use it as a backing board or for taping and stretching watercolor paper. If sanded, a moderate mechanical bond can help adhere acrylic gesso for painting, but since most masonite is tempered (coated with oil and exposed to heat) it is probably not the most archival support for direct application.
Masonite is durable, resistant to warping, and easy to frame.