Long-term gear review | Mammut Broad Peak II down jacket

Small, lightweight, compactly stowable down jackets are a real luxury that, once experienced, you won't want to do without. Usually completely stowable in one of the jacket pockets and, thanks to their low weight, not really a bulky item, these small insulation wonders are practical companions for all mountain activities and, last but not least, a useful resource in emergency situations. It is therefore hardly surprising that this type of jacket is booming and that almost every well-known manufacturer has something of this type in its range. The Mammut Broad Peak II was able to impress in our endurance test.

The jacket is whipped out of the backpack in no time at all and I sit down with the others to rest at the summit, snug and warm. The disparaging smiles at my material fetish quickly give way to envious glances and by the end, everyone would happily swap places with me. I sit too contentedly in a relaxed position while the others trim their hoods and wrap their arms around their bodies.

The fact that this cuddly luxury with only ~370 grams and the pack size of a well-stocked pipe bag fits easily into any touring luggage ultimately convinces everyone, and the unanimous tenor is: "I could do with something like that' too".

The jacket in detail and in practice

The fact that the Mammut Broad Peak II is so convincing in terms of weight, pack size and warmth is of course first and foremost due to the finest 90/10 down with 750 cuin fill power, but also to a good, close-fitting cut, elastic but soft cuffs on the sleeves and adjustable waistband, which keep the warmth in, as well as a successful quilting that ensures that the down remains well distributed without creating noticeable cold bridges. The collar encloses the neck high enough and fits snugly without constricting.

The jacket closes with a 2-way front zipper, although I never needed the opening option from the bottom. At most, the collar is open. Two side pockets and a chest pocket complete the jacket's simple functionality. The fact that the side pockets can't be closed doesn't interfere with handling - because you're unlikely to stow anything permanently in a jacket like this - or, interestingly, with the thermal performance. The spacious chest pocket is equipped with a zipper that can be operated on both sides, as the entire jacket can be stowed in it when turned inside out, making it about the size of a conventional first aid kit when compressed. However, closing the zipper is a little fiddly.

And you often need one. Because as useful as a compact, stowable insulating jacket can be, its all-round suitability is naturally limited. Despite being waterproofed, the jacket naturally cannot withstand constant rain and even if the light, thin outer fabric is surprisingly windproof, a proper hardshell jacket on top increases the weather resistance enormously and improves the insulation even more. However, expecting more from such a down jacket would be completely exaggerated and unjustified. You should just be aware of these limits in the range of use.

Another limit is the limited suitability for high levels of activity. If you sweat a lot, the down becomes damp and sticky and can then no longer provide its insulation performance. In such situations, however, it is advisable to get rid of your warm clothes anyway. You also need to be careful if you want to wrap up warm after a sweaty climb, for example. If your clothes or back are still damp underneath when you put your jacket on, and if you then lean your back against something, the down will stick together and your back will remain cold. It is therefore worth sweating out first and then warming up.

Of course, the jacket is also less warm when compressed, e.g. under the shoulder straps and back when carrying a heavy backpack. However, as the backpack itself usually compensates for this, this has never bothered me. You have to be aware of these limitations of down and if you are looking for a warm jacket for more active use, it is better to use synthetic fiber fillings such as Primaloft or similar. But in terms of weight and pack size in relation to thermal performance, good down simply has the edge.

What can be criticized about the Mammut Broad Peak II, however, is that the outer fabric lets a relatively large amount of feathers through. You always look a bit like a plucked chicken. However, this has never been noticeable in the weight, volume or thermal performance of the jacket during a year and a half of use and is therefore purely cosmetic. Despite the thin materials and really frequent use (it is now almost always with me), the jacket shows little wear and tear, which is of course partly due to its use in mostly passive situations. Nevertheless, I am positively surprised by its durability.

Conclusion

If you're looking for a jacket that will keep you warm, especially when you're resting on the mountain and otherwise disappears in your backpack, the Mammut Broad Peak II is a faithful, warm companion that can really go anywhere thanks to its small pack size and weight.

Advantages:
+ packs down small
+ very light
+ very warm
+ simple but well thought-out
+ cozy, warm collar and snug pockets for your hands

Disadvantages:
- only limited weather resistance
- only partially suitable for activities
- not very robust

Technical data

Fabric: Pertex Quantum (water-repellent)
Filling: 110g 90/10 goose down 750 cuin
Weight: 370 grams (weighed)
Pack size: approx. 24 x 15 x 8 cm
Features: 2-way front zipper with storm flap; 1 chest pocket with zipper (jacket can be stowed in front pocket); 2 side pockets; adjustable hem drawcord
RRP: 250,- € / 330,- SFr

To the manufacturer's product information