20F Mummy Sleeping Bag DISC

$519.00 USD Weight 22.0 oz / 625.0 g
Lead Time Ships in 1-3 Days

*Mummy Sleeping Bags can now be found here*

When a full day of adventure has earned you a good night’s rest, you deserve a sleeping bag that fits like a dream. Our Mummy Sleeping Bag is warm, comfortable, and versatile. It keeps you cozy and tucked away after a long day of hiking, climbing, biking, canoeing or any other outdoor pursuit.

The Mummy features a hood and a full length 2-way side zipper with an integrated draft tube and zipper guard to keep it breeze-free. The zipper wraps all the around the footbox allowing you to open the bag flat like a blanket or to simply unzip the bottom to kick your feet out if you get too hot under all of that premium goose down.

  • Constructed with responsibly sourced and 'Responsible Down Standard' certified DownTek PCF-FREE water-resistant 900 fill power goose down which stays dry 90% longer than untreated down.
  • Each compartment is overstuffed with 30% more 900 Fill Power Premium Goose Down than is necessary for maximum loft to account for any future down compression.
  • Vertical baffles on the upper body keep down from migrating to the sides. Tightly spaced compartments help keep the down evenly distributed so there are no cold spots. There are no "sewn through" seams.  
  • Our rectangular foot box is roomy, and fits the shape of your feet comfortably when lying on your side, on your stomach, or on your back with your feet angled out in a relaxed position. 
  • Black fabric on the inside for quick drying. Both the liner and the shell are treated with PFC Free C0 durable water repellent to resist rain spray and body moisture. 
  • Integrated hood with cinch cord provides full protection from the elements for cold nights on trail.
  • Full length two way side zipper extends around the bottom of the bag allowing you to fully open the bag like a blanket.
  • You can open the bottom end and vent your feet, or flip the bag around and wear it as a cape in camp on cold mornings.
  • A draft tube stops cold air from passing through the zipper. 
  • A zipper guard is in place to prevent the zipper from snagging on the draft tube or sleeping bag material.
  • A snap at the top of the zipper keeps the zipper securely closed.   
  • Our mummy bag maintains its full width at the neck/shoulders. You can hang your arms out to vent, or reach out without unzipping or feeling trapped in a straight jacket like many other ultralight mummy bags.
  • An Elastic cord can be cinched tight around your neck to keep out drafts, or pull the bag up around your ears.
  • Shock cord can be cinched independently at the neck and hood to keep out drafts and snug the hood down around your face.
  • Roll Top Dry Bag is included, and adds ~.9 ounces (25.5 grams) to the listed weight. The dry bags are a comfortable fit and can be compressed smaller by squishing the contents and rolling the top down more.
  • All Zpacks gear has a two year limited warranty against defects in materials or workmanship. Please see our return / warranty policy.
  • Our sleeping bag shell materials do not contain any harmful chemicals such as flame retardants. Our shell is treated with C0 Durable Water Repellent, which is free of PFOA and PFOs


A printable .pdf version is available here.

ISO Rating

While our sleeping bags and quilts have not been tested for their International Standard Organization (ISO) rating, we estimate based on feedback and use that they are closest to the  ISO "Transition Range.“

.51 oz/sqyd Ventum Ripstop Nylon

The inner and outer shells of our Sleeping Bags and Quilts are both made from this super light, high quality, 7 denier fabric that weighs in at just .51 oz/sqyd (17 g/m²). 

Featuring a high quality "C0" durable water repellant (DWR), this ripstop and tear resistant material can also handle light mist and dew (but is not waterproof).

Ventum nylon cuts the wind while still allowing for excellent vapor transfer and breathability. With a soft texture, Ventum is not sticky or plastic feeling like some other fabrics in this weight range.

The material is down and mosquito proof and is an excellent choice for wind shell clothing and sleeping bag shells.

Ventum fabric tests at 39.5 CFM under ASTM D-737.


DownTek 900 Fill Power Water Repellent Goose Down

DownTek 900 Fill power goose down has a "C0" water repellent which allows it to stay dry over 90% longer than untreated down. The water repellent is PFOA and PFOS free. It is 'Responsible Down Standard' certified, ensuring that the animals are treated humanely. Goose down is a byproduct of the goose meat industry.



A printable .pdf version is available here.

Click here for full instructions on how to wash our down sleeping bags and quilts.