Safeguards firearms and other valuables from mold and mildew; Eliminates humidity in enclosed spaces up to 333 cubic feet; Quick-connect bracket makes mounting unit easy in gun safes, closets or pantries; Removes humidity without electricity or batteries; Color-shifting moisture-control crystals signal when recharging is necessary; Simply plug in to dry out crystals and recharge unit for renewed effectiveness; Contains no harmful chemicals - child, pet and home safe; Dimensions: 1.5" x 4" x 6"