Sleep systems

Everest: System 1

This system is a serious weight-saver. Wearing your down suit inside the Hispar 600 moves the performance rating right up to -47°C (the bag in the system is the Wide version to make sure that the suit can loft fully). Yet the Hispar bag weighs around 600g (21.2oz) less than a standard bag rated to -47°C and packs down to about two-thirds the volume. The Hispar 600K has even more impressive stats.
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.
-47°C / -52.6°F
Schematic representation of Sleep System. Actual components differ.
“This bag has an unmatched warmth/weight ratio.”

Features

  • System Products:
    • ​Main Sleeping Bag: Hispar 600 (Wide) (Sleep Rating: -21°C / -5.8°F)
    • Plus Items:
      • Xero Down Suit
      • Xero Down Socks
  • Full System Sleep Rating: -47°C (-52.6°F)
  • Sleeping Bag Weights:
    • Hispar 600 Down Sleeping Bag (Wide): 1154g (40.7oz)
    • Standard lightweight Sleeping Bag to achieve Full System warmth: 1760g (62.1oz)

Description:

This system is very similar to the one already used successfully on Broad Peak (see Case Study), but it advises a much warmer sleeping bag. In theory a Hispar 400 would do (the 400 has a similar rating to the Hispar Overbag used on Broad Peak), but the Hispar 600 only weighs a little over 200g (7.1oz) more and gives a greatly increased margin for mishap or bad weather.

As climbing kit, the Xero suit has summited on Everest before. It also doubles as the night-time booster which shifts the performance figure for the Hispar 600 from -21°C (-5.8°F) up to -47°C. The Hispar bag should be enough for lower camps by itself, but combined with the Xero gear it will provide enough warmth for comfort and safety at Top Camp on any route on the mountain.

K SeriesThe Hispar 600K Down Sleeping Bag (Wide) is available in the K Series. The exceptional loft of 1000 down reduces the weight to just 982g (34.6oz), creating a unique sleeping bag that still fulfils its -21°C rating at under a kilo pack weight.

This review relates to Hispar 600 Down Sleeping Bag

"This bag has an unmatched warmth/weight ratio ... The draft tubes undoubtedly provide the best insulation behind the zip of all the bags tested – not a trivial detail if you face harsh conditions."
from Carnets d'Aventures Magazine's test of 18 sleeping bags for cold conditions.

This review relates to Xero Down Suit

"Fantastic ... felt toasty at -25°C even when the wind picked up. It was a pleasure to live in them day and night."
Olga Kotova - using Xero down suit on Everest. Olga was the first woman from a Baltic State to summit Everest.

This review relates to Xero Down Socks

"The Xero booties were great for sleeping in and I could also wear them inside my Sportivas for mooching around camp. All in all, perfect."
Nick Lewis, Antarctic Logistics & Expeditions.

Sleep system components