Light and compact + three-zipper system for ventilationThe Ascent down mummy sleeping bag redefines the meaning of versatile. Complex construction and high-quality down keep you warm when it's cold outside, while the triple-zipper Free-Flow Zip system ensures you stay cool and ventilated when the weather warms.Shaped to allow a natural sleeping position for comfort, while light and compact enough to go anywhere.Features: ULTRA-DRY Down 750+ Loft 90% Down Cluster Premium Duck Down certified Responsible Down Standard (RDS) Free-flow zipper system: full-length YKK #5 main side zip, half-length opposite side zip, and foot zip provides unparalleled ventilation and use as a comforter Vertical baffles over the chest to prevent down shifting as you roll over in your sleep Shaped hood, oversized draft collar, and zipper draft tube keep the cold out and the warmth in Internal pocket for phone / GPS / valuables Includes lightweight Ultra-Sil compression bag and storage cell Form a snug double sleeping bag by zipping to any Altitude, Journey or Venture sleeping bagTech Specs: Design Type: Backpacking Comes With: Ultra-Sil compression bag and storage cel Insulation: Ultra-Dry Down 750+ Loft Shape: Relaxed Mummy Sheel Fabric: Lightweight 20D Nylon Shell Zip Options: Free-Flow zipper systemMeasurements: Bag Weight: 1100g Compressed Vol (ASTM Standard): 6.2 L Compression Sack: S - 10L to 3.3L Fill Weight: 550g Fits Up To Height: 183 cm Season Rating: 3 Season Temperature Rating (EN Lower Limit): -10oC