TOP TOP-300 Renewable/Rechargeable Wireless Mini Dehumidifier w/Moisture Indicator-Suited for Camera Storage, Closet, Jewelry Box, Lockers and Gun/Document Safes Fights dampness & humidity for an enclosed volume of 500 cubic feet Works W/Silica gel: no batteries or plug-in power needed (while operating) Renewable by Plugging in wall AC Out let to recharge crystals Silently operates for up to 2 months before needing recharge (depending on the humidity in the environment) Spill- & mess-free, non toxic, and child- & pet-safe