Sleep systems

Alps Summer: System 2

This system delivers great performance on the mountain and around camp as well as boosting the performance of the Hispar 400 from -9°C right up to -20°C if you need it. Don’t worry 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)
    • Plus Items
      • Alpine Ultra Jacket
      • Minimus Down Trousers
      • Minimus Down Socks
  • Full System Sleep Rating: -20°C (-4°F)
  • Sleeping Bag Weights:
    • Hispar 400 Down Sleeping Bag: 790g (27.9oz)
    • Standard lightweight Sleeping Bag to achieve Full System warmth: 1050g (37oz)


The Hispar bag by itself is rated at -9°C, warm enough for most summer camps in Europe or at low altitudes (like Baffin or coastal Greenland). 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’, the best for climb or bivvy. Great gear on the hill, but ideal around camp too. Cold evenings feel quite different with down jacket and trousers on, and if night temperatures dip unexpectedly, simply keep them on 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 Minimus Down Trousers

Backpacking Light - Highly recommended

"Overall Rating: Highly Recommended. These down pants are simple and light, just the way we want them. They have the most loft and highest loft:weight ratio of the three pants we tested; I couldn't ask for more. I found that I could extend the warmth of a 30°F (-1°C) sleeping bag to 15°F (-9°C) by wearing these pants and a lightweight down jacket inside."
Will Rietveld, Backpacking Light. Read full review.

Review relates to Minimus Down Socks

"The Minimus trousers and socks are amazing. The combination of weight, compressed volume and insulation properties is outstanding. With down I was able to reduce my pack weight significantly."

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 £174.00 90g
Unbelievably light down-filled sock for warm feet in cold tents.