The Simple Bivy from The North Face is a minimalist bivy sack with clamshell entrance and mesh zipper panel for over the face. At only 1 pound, the Simple Bivy is a makeshift shelter that you can always take with you on the trail. Constructed of The North Face's new DryWall material, this bivy will provide great weather protection while being amazingly breathable. If you are worried about this bag flying away in a storm, The North Face has made sure to attach four exterior loops so that you can stake it to the ground.