This double mat gives a special touch to school diplomas, professional certifications and other important documents that you want to frame for posterity. The mat adds a layer of air between your document and the glass to keep it from sticking due to humidity and age, while the acid-free properties of the mat will not yellow or destroy the document over time. The inner edge of the mat is cut with a beveled edge. Details: Available in multiple colors 8.5" x 11" (21.59cm x 27.94cm) opening 11" x 14" (27.94cm x 35.56cm) total size Recycled core Double mat Acid free