Down 'N Dirty: Mammut Trea Spine 50
93%Overall Score
Durability 95%
Versatility 89%
Comfort 96%
Features 94%
Value 92%

I first stumbled upon the Mammut Trea Spine 50 while looking for a new ski mountaineering pack, and it’s since become my go-to for road trips, mountaineering objectives and winter hut trips. While not a traditional ski bag, the Trea had most of the features I was looking for in an overnight ski pack, plus some mountaineering features that have proven extremely useful on long trips. It has tons of gear hauling capabilities, with loops and straps to carry two ice axes, hiking poles, or skis, and the top pocket is spacious enough to hold my lunch, map, sunglasses and GPS device. The 50-liter capacity holds more than enough for a hut trip–we fit dinner for 16 people without skimping on weekend essentials–and the pack cinches down really well when you dump your belongings and head out for a few mellow laps.

The Active SPINE technology allows the frame to rotate while you’re hiking or skiing, creating a full range of motion that feels way more natural than a rigid pack, as well as distributing weight more evenly across your shoulders and hips. The external spine adjustment also allows you to adjust it from a small frame up to a large frame, which is amazing when you’re trading off a heavier load with a climbing partner who is not the same size.

MSRP: $349

Pros: Large packs can be hard to get in and out of, but the Trea has a huge front zipper that opens up to the main compartment and feels like you’re opening up a duffel bag. The rotating spine technology really makes a difference on long days in the mountains–it’s often tough to ski very naturally with a pack that large, and I almost forgot it was on my back while skiing a few short laps right out the door of the Peter Estin Hut. The pack itself is also pretty light considering its size and the sturdy material it’s constructed with.   

Cons: Because it’s not a ski-specific backpack, there’s not a great place for a shovel and probe. It fits in the front pocket of the main compartment, but it’s not nearly as intuitive or accessible as a traditional ski pack. Also, while I love the frame adjustment, I can’t speak to how durable it might be in the long run, especially with a pack like this that will likely see quite a bit of rugged activity.

Where We Took It: A backcountry hut trip in the Sawatch Range, road tripping through the Rockies, and mountaineering in the Alps.