The Thunderhead Roll Top Dry Bag is designed to withstand whatever you throw at it. If reliability is rooted in simplicity, it doesn't get more reliable than the Thunderhead Roll Top Dry Bag. Make no mistake though, those extra layers you packed for camp will remain dry through everything from a small summer shower, to an unexpectedly bumpy ride down the river. Forget about rips and tears. Constructed with 900D TPU coated NewStream fabric, the Thunderhead Roll Top Dry Bag is designed to withstand whatever you throw at it.