MTM 30 Cal Plastic Ammo Cans are a 100% Polypropylene Plastic and feature a water resistant O-ring seal with a heavy duty latching system and double padlock tab. The ammo cans are also stack-able and make for a great prepper/survival item. The MTM Survivor Plastic Dry Box is a 100% polypropylene plastic and features a built in compass and signaling mirror. This survival box is water resistant with an O-ring seal, triple latching system and double pad lock tabbed. The box fits great into backpacks and gear bags and is great for the outdoors.