You simply can't buy a better sleeping bag, and we would know. Rated to 15 deg F and weighing in at less than two pounds, the bag contains the highest quality, highest fill-power goose down there is. Pertex Quantum face fabric is water-repellent, and breathable, yet dense enough to resist rips and punctures. Updated with our Down Defender treatment offering an extra level of moisture protection for sleeping bags exposed to wet environments. Flow Gate Construction allows warm air to circulate without allowing the down to shift.