Filter Pack BUFF® - 30 units - Adult. Pack of replacement filters designed for BUFF® Filter Mask (Adult Size). Highly breathable to ensure your comfort in daily activities. Triple-layer construction, 98% bacterial filtration efficiency, and water repellent properties. Non-reusable filters, 24 hours of maximum recommended use. Totally binder-free, latex-free, glue-free, fiberglass-free. Design: Solid. Size: Adults.