Our review of the Marmot Helium

The Marmot Helium comes with certified down fill to guarantee an ethical origin; but additionally the shell fabric of the Helium is made from 100% recycled fabrics.

The bag lofts well and quickly when unpacked, and there is a very quick feeling of feedback – warmth from the bag – against bare skin when you climb in.

The Helium is quite a neat fit but doesn’t feel restrictive, and I found enough leg and arm movement to keep comfortable.

The foot box is very well-shaped and warm as is the hood, which is large, well-insulated and can be cinched in with an external drawcord.

The access zip is easy to operate but snags frequently despite an anti-snag strip running down its length.

The Helium is not alone here; anti-snagging on a sleeping bag zip is solved most often by the user’s technique.

The internal pocket falls perfectly where my hand moves across my chest, meaning I could get to my headtorch quickly.

There’s no shoulder baffle and there’s no drawcord at your chest or under your chin, so it’s not possible to completely seal the bag whilst you’re in it other than by cinching the hood right down.

There’s a short zip on the opposite side of the main zip allowing a flap to be folded down allowing free arm movement at camp whilst staying zipped inside the bag. The DWR-treated shell fabric sheds spills very well.

See more sleeping bags in our comparative test here