Wetsuits are made for a wide variety of uses including Snorkeling, Water Skiing, Surfing, Jet Skiing and of course SCUBA Diving. Most suits are completely interchangeable between sports � the 3mm Shorty that you use Scuba Diving today in Hawaii can be used next weekend back home water-skiing. Wetsuits are made of neoprene, a porous material containing literally millions of tiny bubbles. A wetsuit must fit snugly if it is to be an effective at keeping you warm. We have a chart on our site: View Wetsuit Fit for more info. If in doubt, always buy a wetsuit slightly warmer than your needs. If your wetsuit is keeping you too warm you can always let water in to cool you down by slightly unzipping the suit. But if you are cold during a dive there is not much you can do except stop diving.