“Portable Hydration System”: is that just fancy talk for a plastic water bottle? Oh ye of little faith, we’re talking system, here. The hydration pack was especially designed for winter sports and is a nigh-necessity for cross country skiers who tend to work up a sweat in even the coldest temperatures. Worn like a backpack under a jacket, it's insulated (the water won’t freeze), and can hold 50 fluid ounces of water that the wearer sips through a tube over their shoulder. It’s the bottle-free wa...more