Sleep systems

Aconcagua: System 1

The Hispar 500 sleeping bag and the Hispar jacket are both high mountain lightweights that make a great team for peaks around 7000m like Aconcagua. The jacket is rated at -30°C (-22°F) for your ascent. Wear it inside the wide-cut bag at night (along with the trousers and socks) and you'll boost the bag rating all the way 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)
    • Plus Items:
      • Hispar Down Jacket
      • Rondoy Down Trousers
      • Minimus Down Socks
  • Full System Sleep Rating: -35°C (-31°F)
  • Sleeping Bag Weights:
    • Hispar 500 Down Sleeping Bag (Wide): 1016g (35.8oz)
    • Standard lightweight Sleeping Bag to achieve Full System warmth: 1500g (52.9oz)




The Hispar 500 offers astonishing performance for a sleeping bag weighing around a kilo (only 855g for the K Series version). And there’s no need to carry anything heavier if you use this simple system and wear the down gear inside the bag – that will keep you warm down to -35°C, enough for top camp on any route on the mountain with a margin for bad weather thrown in.

For the ascent the Hispar jacket is a high mountain ultralight (the K version weighs just 575g), but it’s rated at -30°C (-22°F), even warmer if you’re wearing fleece underneath. And if the weather’s cold, you’ll be glad of the Rondoy trousers at camps from the Plaza Argentina upwards as well as on the route.

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 Rondoy Down Trousers

"The lightest 'big mountain' down legwear that PHD has produced. They use 950 fill down, water-resistant Ultrashell face material and have full-length side-zips for ease of use. Serious cold weather trousers."
OutdoorsMagic Review.

Review relates to Minimus Down Socks

"Thank you for the fantastic equipment. Everything (including the Minimus Down Socks) was above and beyond what was required and fended off the elements perfectly."
Graham B., on a trip to Aconcagua.

Sleep system components