SnapSafe Rechargeable Medium Gun Safe Dehumidifier - Absorb humidity and prevent rust or mildew in gun safes, closets, pantries and other enclosed areas. Moisture-control crystals change from orange to green, indicating when the unit needs recharging. Dry out and recharge the crystals by plugging into 110V electrical outlet until crystals turn orange again. Effective In Spaces Up To 333 Cubic Feet Absorbs Humidity From Enclosed Areas And Helps Prevent Mold And Mildew Perfect For Closets, Gun Safes, Pantries And Other Enclosed Areas No Cords Are Needed For The Dehumidifier To Work Moisture-control Crystals Change Color To Indicate When The Unit Needs Recharging Simply Plug-in To Recharge And Dry Out The Crystals For Continued Use Contains No Harmful Chemicals And Is Child, Pet, And Home Safe