Crescent - Ragmat - 32x40 - Sable - Crescent RagMat Boards have a 100% Cotton core and backing paper, are acid-free and lignin-free, and come in a wide variety of colors. Crescent RagMat offers a high level of conservation protection. Recommended for fine art prints, limited edition prints, valuable documents, photographs and heirloom needle art. Cotton RagMat is the only matboard guaranteed safe next to any artwork. It is the natural choice when the highest levels of protection are required.