Cotton RagMat is... QUALITY: Cotton RagMat is the only mounting and matting board guaranteed safe next to any artwork. The quality of cotton RagMat is simply unsurpassed and is the natural choice when the highest levels of protection are required. NATURAL: Cotton is naturally acid-free and lignin-free. Cotton RagMat is processed without harsh chemicals or additives. TIME-TESTED: For over 1500 years cotton has been both the courier and curator of history. Priceless documents such as the Gutenberg Bible, Shakespeare's first folio, and the U.S. Constitution and Bill of Rights exist today because they were penned on cotton paper. ENVIRONMENTALLY FRIENDLY: Cotton is an annually renewable resource. Cotton Rag-Mat is processed without harsh chemicals or additives. TRUSTED: Cotton is preferred by museums and preservationists and has been trusted by artists, historians and writers for centuries. GUARANTEED: Cotton RagMat is guaranteed safe next to artwork. RagMat is the only matting and mounting board backed by a lifetime warranty. RagMat meets museum conservation standards as set by the Fine Arts Trade Guild. Made of strong cotton fibers, which are naturally acid-free and lignin-free it is also is annually renewable and environmentally friendly. Cotton RagMat is the only matboard guaranteed safe next to any artwork. • Facing papers exceed minimum standards for fade and bleed as set by F.A.C.T.S. and F.A.T.G. • pH 8.5 - 9.5 • Buffered with calcium carbonate to an alkaline reserve of 3 -5% (except RagMat Museum Solids - Unbuffered) • 4 ply and 8 ply thicknesses. (Consult color specifier) • Meets Museum Standards as set by F.A.C.T.S. and F.A.T.G. Intended for: • Valuable works of original art • Surface papers are pigmented for fade and bleed resistance. • Items of historical importance