The Western Mountaineering Puma is filled with 36oz. of down creating 9" of loft, two densely packed Interlocking Draft Tubes and a full down filled collar will keep you in the ring of fire till 25 below zero. Its VBlock Side Baffle provides phenomenal down control, so necessary in a bag with this much loft. You get a 64" shoulder girth so that there's even room for layering. The MicroLite XP™ shell has superior breathability while being extremely water resistant. This bundle of warmth weighs in at just 3 lb. 7 oz. total weight.