Sleep systems

Trekking Peaks: System 2

The Rondoy clothing is rated for -20°C daytime use, warm enough for your peak. Wear it inside the Hispar 500 and the combination will take care of your nights right down to -33°C. This system is based on a warmer bag and lighter clothing than System 1: overall performance is similar.
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.
-33°C / -27.4°F
Schematic representation of Sleep System. Actual components differ.


  • System Products:
    • Main Sleeping Bag: Hispar 500 (Wide) (Sleep Rating: -15°C / 5°F)
    • Plus Items:
      • Rondoy Down Jacket
      • Rondoy Down Trousers
      • Minimus Down Socks
  • Full System Sleep Rating: -33°C (-27.4°F)
  • Sleeping Bag Weights:
    • Hispar 500 Down Sleeping Bag (Wide): 1016g (35.8oz)
    • Standard lightweight Sleeping Bag to achieve Full System warmth: 1450g (51.1oz)


The Hispar 500 is an amazing bag. Its -15°C performance is possibly enough for your high camp on its own. But no need to take the risk of a temperature drop. Wear your Rondoy summit gear inside the bag and you’ll increase performance to around -30°C. 

For the ascent the Rondoy jacket itself is a superb mountain lightweight offering great warmth for its weight (the K series Rondoy weighs only 500g!).

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 (30oz).

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 Rondoy Down Jacket

"The jackets were incredibly warm and light, equally suited to ensure we were warm when climbing and even when static, melting snow, in the advance camps."
Jonathan Phillips, Imperial College, Obra Valley Expedition (GARHWAL HIMALAYA, INDIA).

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

Works well with
From £828.00 915g -15℃
Mountain lightweight for cold conditions. Ideal for fast ascents and quick travel.
From £830.00 620g -20℃
A lightweight mountaineers' and trekkers' Jacket for the 6000m Himalayan peaks, the high Andes, and the Winter Alps. Now also available in custom sizes.
From £585.00 400g -20℃
Our lightest big mountain and high-altitude trekking down-filled trousers. Now also available in custom sizes.
From £174.00 90g
Unbelievably light down-filled sock for warm feet in cold tents.