Mammut Trion Nordwand 15

A sleek, vest-style daypack that blends trail-running comfort with the technical features climbers need—ideal for fast missions in the mountains or long multi-pitch routes.

The idea of using running vests for climbing/alpinism is nothing new, but it’s certainly gaining more traction, particularly with the rise of fast & light styles such as ‘Speed Mountaineering’ and ‘Trailpinism’ (checkout Alastair McDowell, Rose Pearson & Hamish Fleming’s video of Mt Aspiring in a day). Because of this, we’re beginning to see more companies developing hybrid vest-packs that combine suspension systems from running vests with technical fabrics and features from climbing packs. They tend to be tougher and more weather resistant than traditional running vests, with dedicated piolet/ice-tool & rope carry options, and a bit more capacity for gear. 

Mountain pursuits aside, these vest-packs also make a ton of sense for multipitch rock climbing (especially bigger IAD ascents), since the vest style suspension is so much comfier and more stable to move in than a traditional climbing daypack. To test this out, I wore the Trion 15 during a 3-day ascent of ‘The Dreamliner’ on Airport Wall in Milford Sound, NZ.

Even with all the new options in climbing vest-packs, there aren’t many that tick all the boxes for me (unless you go custom or really expensive like Samaya & Alpinist Lab). So after a lot of hunting around, the Trion 15 seemed to tick the most. It’s got a 15L body made from water-resistant fabric, with a rolltop closure and water-resistant side zippers that access the main compartment on one side, and a separate side pocket on the other side. Having these two sides zippers is awesome for accessing gear quickly, but I wish they had marked them with different coloured zips or pulltabs so it’s immediately obvious which is which. The suspension system stays true to running vests with a fit that hugs the body well (unlike some, which veer a little too close to traditional pack straps). The shoulders also has several mesh pockets that will hold two 500ml soft flasks (or slightly underfilled 600ml Katadyn flasks) and a bunch of bars/gels—but no extra zippered pocket like on the BD Distance 15 or ME Tupilak 14. 

The Trion is also hydration bladder compatible with an internal sleeve and hole for the tube, but everyone knows the cool kids use soft flasks these days. There are two piolet/ice-tool attachments with removable velcro loops for the shafts (these can also carry hiking poles), a removable top strap, and removable side compression straps, which allows you to carry a rope and ice-tools at the same time without it getting too messy. This is another area where some vest-packs fall short, often sharing side compression to secure both the ice-tool shafts (or poles) and rope in place. Some don’t even have side straps, which makes carrying a rope feel frustratingly swingy and insecure (I’m looking at you Rab Latok 20). The rope carry on the Trion 15 is by far the best I’ve experienced on a pack this small, to the point that you almost forget you’re carrying one. The straps and high positioning of the Trion on your back mean the coils are neatly tucked out of the way and don’t bounce/swing around on approaches and scrambles—I was even able to run without it annoying me.

Even on the wall it was very comfortable to climb in and had great freedom of movement, including during harder, more physical pitches where a normal daypack would be annoying and restrictive. This is great, since it allows both the leader and second to carry and have access to their own stuff, with minimal impact on their climbing performance (instead of just bringing one larger, heavier pack that will definitely sandbag the second). Unfortunately this body hugging fit that lets it run & climb so well also comes at the cost of a very sweaty back, but I imagine most people are happy with this trade off. The 15L capacity feels bang on for most people’s use case and provides plenty of room for spare layers, food, water, emergency kit, and whatever else…most of the time. I do sometimes find myself filling it to the brim and not being able to close the roll top properly (I wish it was a bit taller to allow for a few more rolls and some room to overstuff, like the old Arc’teryx Alpha FL packs). If you do find yourself wanting more room, I think it’s worth adding some bungee cord to the daisychains. When not in use, the Trion easily disappears inside my large pack (or haulbag) and at 420g it doesn’t sting too much to pack it.

Final thoughts:

The Trion 15 feels like the perfect blend of running vest comfort and technical climbing pack featues, offering excellent performance on runs/approaches/scrambles and convenient access to water/food/gear. I was particularly impressed with the rope carry system, and just how well it moved with my body while climbing (even while leading harder pitches). My only real complaints were the lack of zippered pockets on the front (which would be handy for small electronics) and the need for a higher roll top when overstuffing. After spending so much time climbing in the Trion, I doubt I’ll ever go back to normal daypacks on long multis. 

RRP: $299.95

Pros:

• Excellent run & climb comfort
• Great rope carry
• Lots of features

Cons: 

• Lacks zippered front pockets
• Roll-top doesn’t overtsuff well

Best suited for:
Those wanting a small daypack to move light and fast in the mountains or long multipitch rock climbs, that has the carry comfort of a running vest and the technical features of a climbing pack.

Overall, I’d rate it 4.75 out of 5 blue offsets

Check out some of our other reviews on Mammut Gear:

Mammut 9.5 Crag Dry Rope