The North Face Assault FutureLight Bivy is a waterproof and breathable light bivy sack. The FutureLight membrane forms the heart of the bivy sack. The wafer-thin network of filaments with countless interlinked air holes between them is produced using nanospinning technology. Thanks to these three-dimensional channels between the fibers, the membrane has more air pockets than other membranes. This allows steam to escape more easily, while at the same time preventing water from getting in from the outside. The technology also ensures good air exchange in the bivy sack. Perfect as a minimalist shelter for (height) mountain sports and expeditions. With space for a sleeping bag, mountain boots and backpack inside.