I bought a plastic ammunition box made by MTM Caseguard. It is slightly larger than the metal military .50 cal. ammo cans. It has a rubber gasket in the lid and a heavy duty pull down latch to pull the gasketed lid down tight. I have the seed separated into classes by card board. Inside is 454 grams of color changing silica gel desiccant. When the gel turns from orange to green, it is time to dry the desiccant in the oven. I purchased the silica gel here: http://www.southernexposure.com/