Controls and prevents musty odors caused by: mold, mildew, dampness, water damage and humidity. Suitable for use in: closets, basements, crawl spaces, attics, sheds, storage containers, moving vaults, storage areas and storage units, during the storage of vehicles, RVs and boats. Controls odors in front loaded washers when used between wash days. Built-in controlled release technology delivers consistently over time (30-365 days, depending on temperature and air flow). One bars treats 5' x 5' x 8' area (200 cubic feet) of still air. Will not damage natural or synthetic materials. Leaves no residue odor. US & International Patents Pending. FREE SHIPPING AND HANDLING (US orders only)!