Prevent condensation from forming inside of Pelican cases, inside of your gun safe, ammo cans, or your food storage. Silica gel is an essential supply for those traveling or living in humid areas because it prevents condensation and absorbs dampness from trapped. . 40 grams Silica Gel Dehumidifier Protects 3 Cubic Feet/85 Liters of Enclosed Space. Reactivate in Oven at 250 Degrees for 3 hours.