Classic cotton stretched canvas is a high-quality, economically priced surface with staple-free edges and key-able corners that allow for tension adjustments. It is stretched using a premium grade 7 oz. acrylic primed cotton canvas, and Masterpiece's MasterWrap technology. The drum-tight, archival surface works great for both oil and acrylic paints. The solid, finger-joint free, kiln-dried bars are sourced from sustainable forests of the Pacific Northwest