Size:1500 This dehumidifier is the perfect addition to your safe, or other areas where you need to control humidity. Stack-On’s Rechargeable Cordless Dehumidifier is a great mini dehumidifier is perfect for use in safes and security cabinets. It absorbs excess moisture without having to drill holes or run electrical cords through your safe. It doesn’t even require batteries. The moisture gauge on the front of the dehumidifier indicates when it needs to be recharged and can pull excess moisture from 100 cubic feet for 4 – 6 weeks before it needs to be recharged. Recharging is easy, just plug it into a standard electrical outlet overnight and this cordless humidifier is ready to go. To refresh the unit, simply plug into a standard 110 electrical outlet or outlet strip there excess moisture can be released and distributed (for example a utility room, garage, well ventilated bathroom). Leave the unit plugged in overnight (8-10 hours).