Silica Gel prevents condensation. And prevents rust, corrosion and spoilage before they begin. Ideal for gun, camera and telescope cases, tool boxes, silver drawers, safes, display cabinets, gun chests, storage containers, plus more. Built-in indicator turns from blue to pink when reactivation is needed. Easily reactivates in a conventional oven. Order ONLINE Today! AVAILABLE SEPARATELY: 450 Gram Silica Gel - word search in our Store for 'Silica Gel'. 40 Gram Silica Gel... Protects 3 cu. ft. of enclosed space. Silica Gel is contained in a compact 4 x 2 x 1/2" aluminum canister.