Ideal for eliminating tobacco smoke from the air in your home, workplace or car. Nature's Air Sponge is non-toxic, biodegradable and environmentally safe. Easy to use, just remove the lid and place where needed. Replace when the contents have shrunk and are no longer blue. This great product also works for cooking odors, pet smells, locker rooms, paint fumes, gasoline, cleaning solvants, mildew and more.