All natural, silver-based antimicrobial additive by Agion prevents the growth of bacteria, mold, fungus and mildew on the binder's surface. Built-in protection. Antimicrobial protection does not wear off and lasts for the life of the binder. Agion's additive is based on silver (not nanosilver)—Nature's Antimicrobial. Agion has global registrations including the EPA and FDA. Clear overlay on front, back and spine for easy customization. Lifetime product guarantee—A Binders for Life product. Locking round rings mounted on back cover allow pages to lie flat while reducing wear and tear. Two clear, inside pockets provide extra storage for loose documents. PVC-free, acid-free and archival-safe.