2015 Ski Guide2015 Ski Guide


The next generation in dry and warm.

Nothing takes the fire out of your engines more than trying to sleep in a soggy down bag, so Sea To Summit designed the ApIII Sleeping Bag to block outside moisture and prevent condensation build-up during long stays at base camp. To achieve this feat, Sea to Summit made this bag with lightweight, breathable outer 3D NanoShell fabric with a Nano-DWR coating and a silicone condensation barrier just inside the shell fabric to expel any moisture that your body creates during the night.
  • Rated down to -4F, this bag is best suited for winter camping, high alpine mountaineering, and ski touring
  • The 850-fill Eastern European goose down gives you superior loft and insulation for a better warmth-to-weight ratio than anything on the planet
  • The 20D polyester shell and lining fabrics provide the perfect mix of softness, durability, and breathability for long expeditions
  • Offset baffle construction, side block baffle, and a 60-40 (top-bottom) fill ratio prevents cold spots
  • Draft tube with lightweight YKK #5 zippers stop heat loss, and the micro anti-snag liner protects the soft inner fabric
  • Adjustable draft collar, cushioned hood, and anatomically tapered footbox keep the down as close as possible to your cold zones
  • An internal zippered chest pocket holds electronics close so your sat-phone batteries don't freeze up overnight
  • Includes a compression sack for trips, a mesh storage sack to preserve loft, and a laundry bag for safe washing once back home

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Sea To Summit ApIII Sleeping Bag: -4 Degree Down

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Here's what others have to say...

4 5

Snug Fit

A review of your Alpine III bag used on Ama Dablam in late November 2011.

First of I am exactly 6' and I initially bought the regular version from Mountain Equipment in Sydney but this was far too short, so I had to replace with the long. This is a very snug bag which has its own advantages and disadvantages.

For a start it is very warm. At 6,000 m in Nepal in late ...November (possibly -20 C), I never closed the zipper the whole way. This big also seems to loft very well. My climbing partner had a Valandre 'Shocking Blue' (from memory) and the Alpine III always seemed to loft better after unpacking. I also was never cold whereas my climbing partner mentioned he slept cold (but then again he had about 5% body fat compared to my 18%.

On the downside, I slept in this bag after spending time in a -40 MH Ghost and I found the Sea2summit very snug. I often take of my thermals in my bag after I have warmed up and this was very difficult to do in the confined space of this bag. I would use this bag at high camps but not at a base camp if you are taking 2 bags on an expedition. One other thing, my bag's zipper at the bottom of the bag, did not work and I was unable to vent by opening this zip. I would check your bag to make sure this is working. The main zip sliding to the hood, is one of the best I have used. Very smooth and rarely snagged.

The little pocket near the collar was great to store my phone and camera batteries at night. I do sometimes wish that sleeping bags designed for very cold conditions had some kind of interna sleeve to store nalgene bottles, so that one can turn in the night without being molested by wayward bottles.

Overall a very warm bag with zero dampness problems. It is snug though so check the sizing.

Snug Fit
Responded on

Notwithstanding all of the great reviews this bag received, I have to agree with the "snug fit" description. There is a reason for this--less interior space = less empty space to heat up. But even though this is a great bag, based on its cut it was not the bag for me. I'm 6"1", 200 lbs., with a 44" chest. I ordered it in a "long." But even with the extra inches, I felt too bound, and so I returned it. I ended up getting the Marmot MemBrain Lithium (a zero degree bag, so not quite as warm, but definitely a better fit for me).

Is it supposed to say -40 instead of -4?

Posted on

Is it supposed to say -40 instead of -4?

Best Answer Responded on

it's -4F, which is the same as -20 celsius