A sudden change in weather, an unforeseen event, or an unplanned night in the mountains: a bivy sack protects you precisely when it matters and is essential gear for any mountaineer. Our Bivy Ultralight is designed for those who spend a lot of time in the mountains and pay attention to every gram. Weighing just 150 grams, our bivy sack has a minimal packed size. The Bivy Ultralight is suitable for one to two people and protects against the elements: it is windproof and, thanks to a PU coating, also water- and dirt-repellent. The silver coating on the inside reflects body heat, keeping the cold out.