Protects your personal belongings from moisture, consumes no energy, refreshes the air, and works without getting dirty. Reduces high relative humidity in enclosed spaces with little or no ventilation. Suitable for RVs, boats, sheds, distribution cabinets, attics, basements, crawl spaces, guest rooms, locker rooms, garden houses, kitchen cabinets, safes, and laundry rooms. Compatible with all Air Max refills: Air Max refill and Air Max tab.