It’s all about staying warm — and the world of exposure protection is making it possible. Super-flexible, ergonomic neoprene designs, and new technology in wetsuits and drysuits mean you’ll stay warmer, longer. First Know This Water steals heat from the body 25 times faster than air, so thermal comfort at depth is directly connected to the type of thermal protection a diver wears. When shopping for a wetsuit, choose a neoprene thickness that best matches the temperatures you’re diving. Then focus on fit. A wetsuit needs to fit snugly without restricting movement or breathing. Also keep in mind that if water can get into the suit, it can get out again, and when it does, it will steal body heat. Pay attention to a suit’s seals — a smooth-skin seal against body skin is the most effective sealing system. Seam stitching is important too — glued and blind-stitched seams stop water entry, making them the best choice for cold-water divers, while flat-seam stitches reduce but don’t eliminate water seepage, making them better suited for warm-water diving. Protective kneepads, anti-chafe overlays, and special linings are all great comfort and convenience bonuses. If the water you’re diving is very cold or if you dive often and regularly enjoy long bottom times, think about investing in a drysuit. There is nothing quite as cozy as spending an hour in 50-degree water wrapped in a warm, fleece undergarment beneath a watertight drysuit filled with air. Shell suits are made from a variety of fabric materials whose thermal properties depend on the thickness of the undergarments. Undergarments also help divers stay warm in neoprene suits — usually compressed neoprene — but these suits also offer inherent thermal properties in the neoprene itself. Some drysuits are bare bones and some are loaded with features, but they are all designed to keep divers warm and dry in a cold, wet environment.