Western Mountaineering Puma MF Sleeping Bag - Rated to -32°C

The Western Mountaineering Puma MF is an expedition-grade down sleeping bag rated to -32°C. It's built for winter mountaineering, high-altitude climbing and arctic conditions – the trips where warmth isn't up for negotiation.

Filled with 850+ fill power goose down and lofting to 24cm (9.5"), the Puma MF keeps you warm through long sub-zero nights. V-Block side baffles hold the down exactly where you need it, dual interlocking draft tubes seal the zip, and a fully insulated draft collar stops heat escaping at the neck. The 20D MicroLite XP™ shell is breathable and water-resistant, so it shrugs off frost and condensation in a tent or bivvy.

Choose it over a lighter WM bag when you're heading somewhere genuinely cold: alpine expeditions, winter bivouacs, high camps. The spacious mummy cut leaves room to sleep in extra layers.

Why you'll love it

• Rated to -32°C – expedition-level warmth
• 850+ fill power goose down – top-end warmth-to-weight and long-term loft
• 24cm (9.5") of loft – serious insulation depth
• V-Block side baffles and dual interlocking draft tubes – even down distribution, no cold spots
• Fully insulated draft collar – seals warmth in at the neck
• Spacious mummy fit – room to layer up inside

Good to know

• Shell: 20D MicroLite XP™, breathable and water-resistant
• Total weight: 1475g (165cm), 1560g (180cm), 1645g (200cm)
• Fill weight: 935g (165cm), 1020g (180cm), 1105g (200cm)
• Girth, shoulder/hip/foot: 157/140/99cm (165cm), 163/142/99cm (180cm), 168/145/99cm (200cm)
• Packed size: 23 x 46cm (165cm), 25 x 50cm (180cm and 200cm)
• Includes an ultralight stuff sack and a breathable mesh storage bag
• Made in the USA

Who it's for

Expedition climbers, winter mountaineers and high-altitude teams who need a bag they can trust at -32°C. It's overkill for three-season use – this is the one for cold-weather bivouacs and arctic conditions.