Designed as both a minimalist bivy sack and a winter sleeping bag cover, Bibler's Winter Bivy adds water-resistance and warmth to any situation. Extremely lightweight, this innovative bivy sack is made of Epic® by Nextec, a breathable, silicone encapsulated polyester ripstop. This fabric allows the Winter Bivy to pack down so small that it can be carried in your jacket pocket. Epic is extremely water resistant, offering protection from short showers, light rain or snow, but is not sufficiently stormproof for long term hard rain. This makes it great as a sleeping bag cover for winter mountaineering, under a tarp as part of an ultralight system, or as a superlight "emergency" shelter for mountain guides, climbers and wilderness travellers. Zippered entry across the shoulders is conveniently positioned for those "delightful" sitting bivies. Sized large to fit over a long winter sleeping bag. Small, lightweight, and totally functional—the new Winter Bivy is a must-have on any wilderness adventure.