Marmot Helium +15 Degree Sleeping Bag
The Helium was a genuinely good bag and the review was right about why: a high fill-power down bag that hit a useful three-season rating at a weight that did not punish you. Marmot has kept the name in the line, revised several times since, so the family is still buyable even though this exact version is not.
What to carry forward from it:
- Fill power is about efficiency, not warmth. 800-fill down gives the same warmth as 600-fill for less weight and bulk; it does not make the bag warmer. The rating does that.
- A +15F bag is a three-season bag for most people, meaning spring to autumn in temperate mountains. Read the comfort figure, not the name.
- A full-length draft tube behind the zip and a proper hood are where a good bag separates from a cheap one of the same rating.
What has improved since: hydrophobic down treatment, which was new when this was written and is now near-universal, and Responsible Down Standard certification, which did not exist and now should.
The care advice that decides whether you own this bag for twenty years or five: never store it compressed. Hang it or keep it in the big cotton sack it came with; the stuff sack is for the trail only. Wash it rarely, in a front-loader, with down-specific soap, and dry it with a couple of tennis balls to break the clumps. A down bag treated that way outlives the person who buys it.
Part of the guide to sleeping bags and pads.