Sleep systems

Alps Summer: System 1

This is a flexible System, with special value if you’re climbing. The Alpine Ultra Jacket and Halfbag are ideal lightweight bivvy gear if you're going to spend nights away from camp, or simply want insurance on a climb. Back in camp they can be worn inside the Hispar 400 to boost its performance from -9°C right up to -20°C when you need it. So no worries about the weather turning cold – you’ll still sleep warm.
Typical Operating Temperature
Guideline minimum temperature. Sleeping Bag TOT: you should get a night’s sleep, under normal circumstances. Clothing TOT: you should feel warm enough, assuming low/moderate activity. Sleep System TOT: relates to full system. For more details, see our Technical Briefing.
-20°C / -4°F
Schematic representation of Sleep System. Actual components differ.


  • System Products:
    • Main Sleeping Bag: Hispar 400 (Sleep Rating: -9°C / 15.8°F) Weight 790g/28oz.
    • Plus Items:
      • Alpine Ultra Down Jacket
      • Alpine Ultra Halfbag
  • Full System Sleep Rating: -20°C (-4°F)


The Hispar bag by itself is rated at -9°C, warm enough for most summer camps in Europe or at low altitudes (like Baffin). The Alpine Ultra gear adds real versatility as well as extra warmth when colder nights call for it. 

One user called the Alpine Ultra jacket ‘the perfect alpine downie’ and combined with the halfbag it makes a super lightweight option for a bivvy (planned or unplanned) down to about -5°C.

If you’re unlucky and the weather turns cold, wear the jacket and halfbag inside the Hispar bag and the system will cope with -20°C. You’ll have the safety of this margin without having to carry a big -20°C sleeping bag.

K Series: The Hispar 400K Sleeping Bag is available in the K Series: performance is the same, but the exceptional loft of 1000 down reduces the weight of the bag to an amazing 655g (23.1oz).

Review relates to Hispar 400 Down Sleeping Bag

"I'm over the moon to say the least. The build quality is excellent and I'm picking the bag up every hour to try and convince my brain that it actually is that light. Consider me a totally satisfied customer, please pass my thanks on to the team."
Rory Abbott.

Review relates to Alpine Ultra Down Jacket

"Alpine Ultra jacket was definitely the "go to" piece of kit for the whole expedition. Quick on, quick off, stuff it in the pack, clip it to an anchor whilst you sort gear. Drishell is durable enough for arm rappels on fixed ropes and definitely proofed enough for high mountain conditions."
Ben Kane, Guide, Field Touring Alpine.

Review relates to Alpine Ultra Halfbag

"The Alpine ultra half bag has been excellent. I'm a great fan of the anorak/half bag combination and have used it for many years – warm enough most of the time in this country (UK). The system is ideal if you tend to fidget about in the night and find sleeping bag entry + zips + keeping tabs on the dog all a faff particularly when it’s wet and easy to get the inside of larger sleeping bags damp."
Mick Roffe.

Sleep system components

Works well with
From £781.00 790g -9℃
Mountain lightweight for cool conditions. Ideal for fast ascents and quick travel.
From £538.00 340g -10℃
A climbers' down jacket at the limits of lightness. Even with chest pockets and the optional helmet-sized hood, it's lighter, warmer and packs smaller than fleece. Now also available in custom sizes.
From £315.00 250g 3℃
Our Alpine half bag (pied d'elephant) to insulate legs and feet. Camp down to 3°C and bivvy down to -10°C (with a suitably warm jacket)