Mammoth Double Sleeping Bag Liner: How to Add Warmth and Wash It
By TETON Sports | Published: 2026-11-03
Category: How-to Guides
Use the Mammoth Double Sleeping Bag Liner to add about 10° of warmth, keep your bag clean, and wash it without clumping or shrinkage.
Quick answer
Lay the Mammoth Double Sleeping Bag Liner inside your Mammoth two-person sleeping bag, secure the Velcro fasteners, and sleep inside the liner. Wash it on a gentle cycle with mild detergent and air-dry it fully before the next trip.
Why a liner helps beyond extra warmth
A liner adds a layer you can wash often, so your sleeping bag stays cleaner and needs fewer deep washes. The Mammoth liner is sized at 91 x 56 inches to fit TETON’s Mammoth two-person bags, which means less bunching than a generic rectangular liner.
The warmth gain is real but modest—about 10°F according to the catalog—so treat it as a comfort boost, not a substitute for a bag rated for the cold you expect.
When a liner is the wrong fix
If you are consistently cold below your bag’s rating, a liner alone may not close the gap. Check your pad’s insulation and your base layers first. Also skip the liner if you dislike extra fabric around your feet or if your bag is already tight—the liner adds bulk inside the bag.
How to use and wash the Mammoth liner
- Lay the bag flat and open: Unzip your Mammoth double sleeping bag completely and spread it flat. Smooth the interior so the liner can be positioned without wrinkles. A flat, unzipped bag is easier to line up than a half-open one.
- Place the liner inside: Lay the Mammoth liner into the bag with the fabric edges matching the bag’s corners. The liner is sized for Mammoth two-person bags, so it should sit without stretching. Check that the liner’s long side runs along the bag’s zipper side.
- Secure the Velcro fasteners: Press the Velcro tabs together at the points provided so the liner stays attached to the bag. Tug gently to confirm it will not slide during the night. If the liner bunches, reopen the bag and reposition before fastening.
- Sleep inside the liner: Slide into the liner rather than lying on top of it. Keep the liner’s opening aligned with the bag’s opening so you can get in and out easily. A liner that is slept in—not on—delivers the warmth and keeps the bag clean.
- Shake out and air before packing: In the morning, pull the liner out, shake off debris, and let it air for a few minutes before stuffing it back with the bag. Air-drying the liner daily reduces moisture inside the bag.
- Wash on a gentle cycle: Remove the liner from the bag and close the Velcro tabs. Machine wash cold on a gentle cycle with mild detergent. Avoid bleach and fabric softener. Closed Velcro tabs prevent the hooks from snagging the fabric.
- Air-dry completely: Hang or lay the liner flat to dry fully before storing it. Do not put it away damp, and avoid high heat, which can damage the fabric. A dry liner prevents mildew and keeps the next night comfortable.
Product facts
- Mammoth Double Sleeping Bag Liner: The Mammoth Double Sleeping Bag Liner is 91 x 56 inches and made to fit TETON’s Mammoth two-person sleeping bags. A liner that matches your bag’s footprint stays put and avoids twisted fabric at your feet.
Mammoth Double Sleeping Bag Liner - Mammoth Double Sleeping Bag Liner: It secures inside the sleeping bag with Velcro fasteners and adds about 10° of warmth. The fasteners keep the liner aligned with your bag, so the warmth layer stays where you need it through the night.
- Mammoth Double Sleeping Bag Liner: The liner is made from soft, breathable fabric and is designed to keep your sleeping bag dry and clean. You can wash the liner more often than the bag, which extends the life of the bag’s insulation.
