Whether you’re planning to climb Everest, trek across Antarctica or are simply anticipating the arrival of the next ice age, the Marmot CWM MemBrain is without question the only sleeping bag that will keep you wishing for more cold. As the most extreme sleeping bag in the Marmot lineup, the CWM MemBrain can withstand temperature drops as low as –40°F in the harshest alpine environments, keeping you warm, toasty and sleeping like a baby, no matter how frigid it may get around you.
Making the magic happen, the Marmot CWM MemBrain is loaded with Marmot’s 800+ fill goose down, carefully selected to provide the most efficient insulation possible. As connoisseurs of down, Marmot relies on a series of guidelines to ensure optimum insulating. Down comes from geese, not ducks, due to goose down’s higher quality; down comes from larger, more mature birds, due to the mature bird down’s larger filament clusters; and down must be properly sorted, washed and dried, to adequately prepare the filament clusters. All of this adds up to down that boasts a higher loft, better insulation, lighter weight and greater durability, meaning your sleeping bag does exactly what it says it does (which in this case, amounts to keeping you alive and happy at –40°F). Marmot doesn’t just talk about their down quality, they guarantee that every sleeping bag they sell has at minimum the down content listed, and they guarantee that your bag will perform exactly as it should, for the life of the product.
Of course, down alone does not a sleeping bag make. Keeping the down in place, and ensuring unpleasant drafts are eliminated, the Marmot CWM MemBrain is over-engineered with reinforced linings, countless baffles and MemBrain waterproof/breathable fabric. Specifically, there’s a 9-baffle chest section that runs vertically, ensuring that as you roll from side to side, the down stays perfectly in place. There’s an 11-baffle foot box that runs vertically to keep your feet warm. There’s a down-filled draft tube that eliminates cold leaks through the zipper. There’s a 6-baffle hood that insulates your head with 6 chambers of down and an easy access hood cord. I could quite literally, go on and on and on about how well the Marmot CWM is insulated. But what it all boils down to is this: the Marmot CWM MemBrain Sleeping Bag is the most rugged, well-designed sleeping bag you’re going to get. I’ve used it in some supremely intense conditions, and I can say without question this thing can handle any weather conditions you can throw at it. It’s exceptionally warm; drafts are non-existent; the multitude of baffles keep the down perfectly in place; and at 4 1/2 pounds, it packs up extremely well. There is no better extreme temperature sleeping bag on the market.
In addition to the features I’ve already detailed, here’s a lengthier rundown of all the Marmot CWM MemBrain’s attributes:
- Filled and Finished in Santa Rosa, California
- Certified 800+ Fill Power Goose Down – Independently Tested and Certified by International Down and Feather Laboratory in Salt Lake City, Utah. Retested at Fill Time in Santa Rosa to Ensure 800 Fill Power Every Time. If the Down Does Not Meet Our In-House Test, We Send It Back
- Marmot MemBrain® Waterproof/Breathable Fabric – Marmot MemBrain, Waterproof/Breathable Fabric
- 9-Baffle Chest Section – Baffles Run Vertically in Core for Maximum Down Control. Rolling from Side-to-Side Won’t Shift the Down
- Reinforced Foot Box Lining – To Handle the Extra Abuse of Boot Liners and Water Bottles
- “Feely” Draw Cords – Ease Nighttime Cord Fumbling
- 11-Baffle Foot Box – Baffles are Vertical to Keep Down Around Your Feet
- Down-Filled Draft Tube – Eliminates Cold Leaks Through the Zipper
- Ground-Level Side Seams – Eliminates Drafts
- Hidden Draft Tube Pocket – Inverts Into Draft Tube and Used to Store Watch or Alarm and Stay Out of Our Face
- Nautilus 6-Baffle Hood – 6 Chambers of Down Around Head for Better Down Control and Fit, Hood Cord is Positioned for Easy Access
- Stretch Tricot Baffles – Provide Ultimate Strength, Durability and Bag Life
- Stuff and Storage Sack Included – Store and Pack Just Like Your Sleeping Bag
- Velcro®-free Down-filled Collar – Keeps Warm Air Trapped in Your Bag; Collar is a Full 6-inch Baffle Width Integrated with the Draft Tube
- Velcro®-free Face Muff – Keeps the Drawcord and Zipper Away from Your Face
- Zipper Guards – Help Repel Biting Zipper Coils
- 6-foot height; also available in sizing up to 6′6″
Pricing for the Marmot CWM MemBrain sleeping bag is set at $679 – a steal considering this is likely the last sleeping bag you’ll every buy for extreme conditions. To learn more about the Marmot CWM MemBrain as well as the full lineup of other fantastic Marmot sleeping bags (I own 2 other Marmots for warmer temperatures that I love equally as much), head over to Marmot.com or buy now from Amazon.com