The Cocoon has one of the best warmth-to-weight ratios in our range, making it a popular choice for the lightweight adventurer. The sumptuous, highly breathable 15-denier Vapour Vent is used as both inner and outer fabric; it’s a real weight saver, as is the body-hugging mummy shape. Your down won’t be going anywhere thanks to the combination of vertical chest baffles and our famous V-baffles, while the 3D hood and neck closure stop your warmth escaping. The flexibility of a full-length zip helps your night time metamorphosis into a well-rested, happy little camper.

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SKU: COCOON Category:

mummy bagvapor vent v2bushwalkingmountaineering
COCOON-11 REGULAR 700+ LOFT DWR 1021 -4° -11° -28° 187 160
800+ LOFT DWR 975
COCOON-11 LARGE 700+ LOFT DWR 1126 -4° -11° -28° 195 178
800+ LOFT DWR 1075
COCOON-8 REGULAR 700+ LOFT DWR 855 -2° -8° -26° 187 160
800+ LOFT DWR 820
COCOON-8 LARGE 700+ LOFT DWR 943 -2° -8° -26° 195 178
800+ LOFT DWR 905
COCOON-5 REGULAR 700+ LOFT DWR 802 -5° -22° 187 160
800+ LOFT DWR 772
COCOON-5 LARGE 700+ LOFT DWR 885 -5° -22° 195 178
800+ LOFT DWR 852
COCOON-2 REGULAR 700+ LOFT DWR 724 -2° -10° 187 160
800+ LOFT DWR 699
COCOON-2 LARGE 700+ LOFT DWR 799 -2° -10° 195 178
800+ LOFT DWR 772

temprating-en13537One Planet sleeping bags are rated using the European Standard EN13537. This means every sleeping bag has two ‘real world’ and one extreme rating. To determine what temperature might be most suitable for you see our technical pages.

  • ‘Comfort’ rating is based on a ‘standard’ woman having a comfortable night’s sleep.
  • ‘Limit of comfort’ is based on the lowest temperature at which a ‘standard’ man is deemed to be able to have a comfortable night’s sleep. This is the figure we use in our product descriptions.
  • ‘Extreme’ rating is a survival rating for a ‘standard’ woman. According to EN 13537, ‘a strong sensation of cold has to be expected and there is a risk of health damage due to hypothermia’. This is a survival rating only, and consumers should not rely on this rating for general use. The best guidelines are the comfort and limit of comfort ratings.

Cocoon sleeping bags come in two sizes. As a general rule our sleeping bags are a little roomier than other brands.

The shoulder circumference measurement gives and indication of how much internal room the sleeping bag provides.

Choosing a sleeping bag, which fits well, will provide the best performance. If you would like more room in your sleeping bag we offer a series of Sleeping Bag Expanders.

One Planet DWR Down

We use two qualities of down in our sleeping bag range.

700+ loft DWR treated duck down is our best value down, used for applications where minimum weight and packed size are not critical. Sleeping bags filled with this down are around $50 cheaper than their 800+ loft counterparts and around 100 grams heavier.

800+ loft DWR treated duck down is our premium choice – a must for the gram counters. This high-lofting white duck down delivers luxurious warmth at a fine feathery weight. This down has excellent compactability and loft recovery.

Down is the best insulation for lightweight sleeping bags due to its loft, compressibility and durability. However, this golden fibre has a failing: its ability to insulate drastically decreases when it is wet.

The solution is now here – DWR DOWN. This down has been selected to meet our rigorous standards, with a durable water-repellent (DWR) treatment applied after the cleaning and sorting process.
The benefits of DWR DOWN are:

  • It absorbs less water in damp conditions
  • It retains higher loft (insulation) in damp conditions
  • It dries faster

Cocoon sleeping bags are filled to order with our 700+ loft DWR Down for great value and 800+ loft DWR Down for greater weight saving.


Cocoon sleeping bags are made using lightweight and highly breathable 20-denier Vapour Vent fabric. This fabric is strong, compressible and highly breathable. Vapour Vent fabric is woven to allow water vapour to escape whilst remaining down proof. This helps to reduce the sensation of being clammy in the sleeping bag and allows the down to loft to its full potential for maximum performance.



The Cocoon series is designed for hiking, lightweight travel and general camping. The tapered rectangle shape provides wiggle room and allows the bag to unzip in to a duvet on warmer nights.


Storage and stuff sacks

Your sleeping bag is delivered in a stuff sack, as this is easiest way to transport it. However, it should not be stored in its stuff sack long-term as this compresses the fill material and may cause damage. Hang the bag in your wardrobe over a large hanger, in the supplied storage bag, an old pillowslip or flat under your bed.

When putting your sleeping bag in its stuff sack, do as its name suggests! Don’t roll or fold it, simply stuff it in with your fist, pushing it down to the bottom of the sack. This allows the fill to settle in pockets rather than being squashed flat.

Be careful not to place excessive force on the compression straps. If the bag is compressed too much, the small feather content can be forced through the sleeping bag’s shell. This fill leakage won’t affect the performance of the bag; it is more a nuisance or cosmetic problem. However, storing your bag in a highly compressed state for long periods will permanently damage the fill material, resulting in an inferior performance.

Cleaning your bag

Washing a down sleeping bag can be a daunting process. However, your bag will perform better for longer if it is kept clean. There are two ways to do this:

Use a professional

This is the easiest way to get your bag clean. One Planet don’t just make the bags, we look after them, too. Send your dirty, bedraggled bag to us and it will come back fresh, clean and fluffy. Too easy! Contact One Planet by email or phone for further details on our services.

If using another professional service, ensure they specialise in cleaning down products.

DIY sleeping bag washing

Fill a bath with enough warm water to cover your sleeping bag and add a small amount of non-detergent soap, we use and recommend Nikwax Down Wash. Be very gentle with your bag when it is laden with water and do not lift it clear of the water.

  • Gently massage the bag, pressing down with your open hands, until the fill material is saturated
  • Leave to soak for one to four hours, depending on the dirtiness of the bag. Drain the water from the bath, add fresh, warm water and repeat the gentle massage.
  • Continue draining and adding fresh, warm water until all the suds have been removed and the water is clear.
  • Drain the bath and, without moving the bag, press water out of the fill material until it has all gone and the bag is merely damp.
  • Fold the damp bag into a bundle so you can manage it by yourself, without letting it sag.
  • Lay the bag in a clean, shady spot and open it out.
  • Regularly massage and separate the drying fill material until an even loft is achieved.
  • In cold, wet or humid weather, the bag may be placed in a small room with a heat source to aid drying. Remember to separate the fill material regularly.
  • A sleeping bag with natural fill will take several days to dry completely. It is important to have good air flow around the bag, and it should be moved regularly to assist the drying process
  • Finish the process by tumble-drying the sleeping bag on low in a commercial sized tumble drier. It is very important to keep the temperature low so you don’t cook your bag