The Sphere is lightweight and warm. The wave-shaped box wall construction is meant to stop the down moving about and cold spots forming. I certainly haven’t noticed any of the latter but then I haven’t in most of the other bags tested either. The shell fabrics are thin and soft and drape well round the body. The hood fits well. However, the Sphere is very close-fitting. I can’t turn over inside it and felt slightly restricted and I’m not heavily built. I think this is a bag for skinny people and those who like a bag to move with them rather than being able to move in it. I also found the zip a little hard to open when under tension, which has once led to a feeling of being trapped when I was too hot inside and couldn’t move for a short while.

If you find the fit comfortable the Sphere is a top quality bag. I prefer a little more room.

First published: July 2013

Overview

  • Overall: 3 out of 5

Pros: light weight, two sizes

Cons: expensive, close fit

  • Details: FILL: 450 grams 850 Fill power goose down SHELL: nylon CONSTRUCTION: wave box wall ZIP: 140cm SIZES: two MAKER'S WEIGHT: 750 grams TESTED WEIGHT: 799 grams MAKER'S RATING: lower comfort for women -1ејC, for men -7ејC WEBSITE: mammut.ch PRICE: Ј370
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