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Sea to Summit says:
Light, warm, comfortable and most importantly, adaptable. The Ascent™ is our sleeping bag of choice for most adventures, most of the time. Offering the perfect backpacking balance of comfort vs weight, our Ascent™ Series sleeping bags have more space than traditional mummy bags, yet still provide the thermal efficiency you need when exploring above the tree-line.
The Free-Flow triple-zip design ensures your sleeping bag retains maximum warmth and efficiency when needed and multiple ventilation options when it’s not. The half zip on the right side of the bag provides freedom of movement for both arms, additional ventilation and means the top third of the bag can be folded down as a mini quilt. The full length, two-way left side zip and separate foot zip transforms the bag into a full quilt for when the mercury climbs higher than expected.
If it’s warmth you’re after, close all the zips, pull the cord locks tight to drag everything in, and relax in luxurious comfort. The generous allocation of high quality 750+ Loft down ensures great insulation, while the oversized draft tubes prevents your body heat escaping. The panelled footbox and 3-dimensional hood make sure you’re not compressing the down when you’re trying to stay
warm. Vertical baffles over the chest section ensure the down insulation cannot migrate or shift to the outside of the bag during sleep, creating cold spots. A side block baffle construction maintains the 60/40 fill ratio, keeping more down on the top of the bag for maximum insulation.