Dry-Packs 300gm Dehumidifier Moisture Indicating Silica Gel Canister 300 Gram Dehumidifier requires no electricity Cobalt Chloride free indicating Silica Gel lets you know when it needs reactivating Protect guns, ammo, sporting goods, electronics, safes, rvs, camping, coins, collections Perfect for tool boxes, safes, gun cabinets, laptop bags, closets, storage bins, shoe boxes, boats and more Easy to reactivate for years of use