Masterpiece 3D Stretched Canvas Thick, dramatic 2-1/2 inch deep heavy duty, keyable stretcher bars are used to make 3D canvas. 3D Stretched Canvas is made of the highest grade cotton 12 oz duck with a medium tooth texture. Gallery wrapped...Large staple free edges make 3D ideal for frameless presentation. Canvas salvage is left on back should you ever like to re-stretch. Hand tailored corners yield a neat, professional appearance without bumps.