The DampRid hi-capacity moisture absorber is the fast, easy and effective way to control moisture in large spaces over extended periods of time. DampRid 's natural crystals effectively control musty odors caused by excess moisture for up to 60 days in areas up to 1000 square feet and up to 6 months in a 250 square feet area, depending on temperature and conditions. It's incredibly easy to use just remove the lid to activate the crystals and place it on a flat surface. The Moisture-Lock technology and sealed safety cover prevent spills and keep children and pets out. And when the crystals have completely dissolved you can just toss it in the trash