Sphere Eigerjoch
Down Sleeping Bag
from £ 589.00
Free Shipping
  • Free shipping
  • 30-day Return period
  • Free Returns
Designed for:
A bivouac box for your backpack. A week bivouacking in Chamonix is about more than just boiling coffee and eating in your sleeping bag. When it comes to equipment, you need to make sure you are carrying only the bare essentials. As you will be packing your down jacket anyway, we have developed the Sphere Eigerjoch sleeping bag, designed to be used mainly in combination with your Eigerjoch Jacket Men or Biwak Jacket Women to create the perfect bivouac sleeping bag. The volume of down, sourced from animal-friendly operations, is reduced in the upper body area to take account of the additional warmth provided by your jacket. To make sure you don’t need to leave your sleeping bag at all on very cold days or during bad weather, it has openings for the arms and a zipper at the bottom to allow you to walk around. An insulating collar retains heat around the feet while the closed hood combines an unrestricted view with effective protection from the cold. With the Sphere Eigerjoch and a good book, you can sit out any storm.


Item no.2410-02050 CutBasic


Inner width in foot area (EN 13537:2012)49 cm Construction typeWave Box Windchill °C-4 °C Windchill °F25 °F Maximum inner width (EN 13537:2012)77 cm Warm collarNo
  • Developed for use with the Eigerjoch Jacket Men and the Biwak Jacket Women
  • Reduced quantity of down on upper body area, so it can be worn under a down jacket
  • Performance Hood with Advanced Visibility: a full view with the hood closed and very good protection against the cold
  • Dual zipper – two half zippers on both sides allow the user to take both arms to read or cook
  • 2-way zipper with optimized anti-snag webbing for ventilation
  • Oversize draft tube: thick zipper flap keeps the warmth inside
  • Internal pocket with Hook and loop fastener
  • Insulation skirt keeps heat in foot area
  • Zipper opening at the bottom allows good ventilation and moving around without leaving the warmth of the sleeping bag
  • Side gear loops to lock open foot part at two different heights
  • All fittings are located on the outside to allow the optimum combination of sleeping bag and down jacket
  • Temperature limit in combination with Eigerjoch / Biwak Jacket: -7 ° C
  • Contains textile products of animal origin (down or leather)

Material & technology

Main Fabric
100% Polyamide
90% White goose down | 10% White goose feather
Lining 2
100% Polyamide
100% Polyamide
Mammut Down 800 cuin Fair Wear


Machine wash on synthetics / permanent press cycle (max. 30° C) Do not dry clean or use solvents to remove stains Tumble dry at low heat Do not use chlorine-based bleach Do not iron or treat with steam

Related products

Shipping costs
Delivery is free of charge from a purchase value of £150 or more. A delivery charge of £6.95 will be applied to orders below this purchase value.

Delivery lead time
We aim to process all orders as quickly as possible - orders placed before 11 am (Mon-Fri) are generally dispatched on the same day. Orders placed after this time are dispatched the next working day at the latest, which means the delivery lead time is generally 2-5 working days. You will receive a dispatch confirmation including a tracking number as soon as we have transferred the order to our logistics partner.

Delivery country
In the online shop for european countries, deliveries can be made only within the following countries: Belgium, the Netherlands, Denmark, Italy, Poland, Slovenia, Slovakia, Spain, Sweden, Czech Republic.

Shipment tracking
Together with the dispatch confirmation, you will receive a tracking number and a link which you can then use to check the status of your parcel.


We will send you an e-mail as soon as the item is available. Information on our data protection policy


We have noticed that you're in the US. Do you want to visit the US shop?