Mountain Hardwear Nitrous&trade; Jacket The two front pockets serve as perfect handwarmers, while the zippered chest pocket provides an excellent spot for storage. Both lightweight and warm, this Jacket features 800-fill down for superior warmth in variable conditions. The one-handed hem draw cord allows for quick adjustments on the Fly, and the full elastic cuffs effectively seal in warmth. with its low profile, it is perfect for layering underneath an outer shell and compresses easily for efficient storage.