Sleep systems

High Mountains: System 2

This system (like System 1) is based on the Hispar 500 sleeping bag and the Hispar jacket, both of them high mountain lightweights that make a great team for peaks around 7000m. As in System 1 the jacket is rated at -30°C for your ascent. But a down halfbag takes the place of trousers and socks inside the Hispar bag at night and along with the jacket provides the same warmth as System 1 right down to -35°C.
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.
-35°C / -31°F
Schematic representation of Sleep System. Actual components differ.
“The Hispar is a totally amazing jacket … Used it on 3 Aconcagua expeditions this season.”


  • System Products:
    • Main Sleeping Bag: Hispar 500 (Wide) (Sleep Rating: -15°C / 5°F) Weight 915g/32oz.
    • Plus Items:
      • Hispar Down Jacket
      • Hispar Half Bag
  • Full System Sleep Rating: -35°C (-31°F)


This variation on System 1 reaches the same max sleep rating of -35°C by using the jacket and halfbag inside the Hispar 500. The halfbag is a simpler and lighter way to achieve this night-time boost than using down trousers and socks (about 150g [5.3oz] lighter), and the halfbag can also be carried as an emergency backup item on the ascent. But it can't keep you warm as you move about camp and it can't perform as legwear on the climb.

K SeriesThe Hispar 500K Sleeping Bag (Wide) 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 855g (30.2oz).

Review relates to Hispar 500 Down Sleeping Bag

"The lightest bag tested yet warmer than some ... The Hispar 500 really does deserve the description 'Ultralight' ... The loft really is astonishing for such a lightweight bag ... the Hispar 500 is my favourite of the bags tested."
Chris Townsend, Winter Down Sleeping Bags test, TGO Magazine.

Review relates to Hispar Down Jacket

"The Hispar is a totally amazing jacket. Really surprised by the warmth it offers. Amazing warmth to weight. Used it on 3 Aconcagua expeditions this season and it was just ideal."
Ben Kane, Guide, Field Touring Alpine.

Review relates to Hispar Half Bag

"This looks amazing. I can see the Hispar bag working incredibly well up to 7000m in combination with the Hispar overbag and a Hispar jacket".
Ben Kane, Field Touring Alpine.

Sleep system components

Works well with
From £828.00 915g -15℃
Mountain lightweight for cold conditions. Ideal for fast ascents and quick travel.
From £923.00 725g -30℃
A high-altitude mountaineering jacket that's incredibly light for its capabilities. Packs down amazingly small too. Now also available in custom sizes.
From £374.00 350g -7℃
Our expedition half bag (pied d'elephant) to insulate legs and feet. Combine with expedition down clothing. Camp down to -7°C and bivvy down to between -15°C and -25°C.