National Geographic Snorkeler accessories are constructed from materials at the leading edge of water-wear technology. The Mariana Trench dry bag clear cylinder 30L is a great way to keep your belongings dry and together. This bag is a must have at the pool, on the beach or on the boat. Empty your pockets into this bag and keep the contents dry and the sand out! This see trough bag makes it easy to locate your belongings without opening the top.