If you need a sub-freezing warmth sleeping bag in the smallest possible size, but also want the comfort of fully opening the bag in warmer climates, the Sea to Summit Micro McIII Sleeping Bag is your bag.Features: Down: ULTRA-DRYDown 850+ Loft 90% Down Cluster Premium European Goose Down 2D NanoShell Differential cut shell Box quilted baffles; 55/45 fill ratio Zipper draft tube with anti-snag Large sized internal zipper pocket Hood drawcord with dual adjustment YKK #5 side zip Drawcord foot closure Length/Zip: Regular - right zip Season ratings: Indoor/Summer/Spring/Autumn Compressed volume: 4.53 Liters - Regular Compression bag: X Small - 6 to 2 Liters Box quilted mummy convertible Includes lightweight Ultra-Sil compression bag, mesh storage cell and laundry bag