A super-lightweight yet comfortable to carry and ruggedly robust backpack is the holy grail for hikers. Does the Simond MT900 Ultralight 50L mean the search is over?
You can be forgiven if you're not overly familiar with the Simond brand. If you've not shopped online or in-store at Decathlon you're unlikely to have come across this French brand. Let's clear something up first: Simond is one of Decathlon's brands, but it isn't a Decathlon brand.
Hmm, perhaps that clarification requires clarification. You see, Decathlon produces its own products, and it gives brand names to these ranges of products, such as Forclaz or Quechua. But Simond is not one of those.
Pros
- Lightweight for its size
- Comfortable padding
- Properly adjustable back system
- Robust
Cons
- Roll-top closure may divide opinion
| RRP: | £230 |
| Weight: | 880g |
| Volume: | 50L |
| Maximum load: | 12kg |
| Storage: | 3 large external pockets, quick-access water bottle holder, internal zippered pocket, 2L hydration bladder compartment |
| Materials: | PA 100D Ripstop, ultra-lightweight alloy |
Founded in Chamonix in the mid 19th century, producing mountaineering equipment such as ice picks, crampons, sleds and skis, Simond did not come under the Decathlon umbrella until 2008, when the latter acquired the former, keeping the brand independent due to its solid mountain heritage. Make sense now?
In 2025, Decathlon is reintroducing Simond to the world "for people that are discovering the brand for the first time", and it's doing so by releasing new products that will make people sit up and take notice, including this Simond MT900 Ultralight 50L...
Although not technically a Decathlon product, the MT900 designation is part of its product identification system, indicating that this pack sits at the upper end of Decathlon's mountain trekking inventory.
This alone suggests that this is a high-performing pack worthy of taking a closer look at. A quick glance at the stats on paper – particularly those relating to the weight of the pack – reaffirms that Simond has done something special with this pack. And you don't have to look too closely to see why…
Simond MT900: Five things you need to know
Ultra lightweight
Making a pack lightweight is easy. Making one that's also comfortable and robust is not. Luckily, Simond has over 150 years of gear producing knowledge to fall back on. With its experience of gear design, fabrics and construction, Simond has produced a 50-litre trekking pack that weighs just 880g.
Every component, from the clips to the straps, has been carefully designed to contribute to the lightness of the bag. Despite this, the MT900 doesn’t skimp on design features.
Yes, it uses a roll-top closure rather than a proper lid, but you still get a hydration pouch sleeve, a steel frame, a proper back panel and multiple pockets for storage.
Great comfort and fit
A pack designed for long-distance routes such as Europe's GR treks has to be comfortable day after day. Making it super-light isn't enough on its own. The shoulder and waistbelt straps are padded with dual-density foam for cushioning and perforated for ventilation.
The back system is a proper one, with a curved suspended mesh panel, and the harness is adjustable for different torso lengths, ensuring a comfortable fit.
Three years in the making
It took the Simond backpack design team years to perfect this model. "Each iteration was a challenge,” says Simond product engineer Bertrand.
“We had to strike the right balance between features and weight. Thanks to field testing, we gathered feedback from trekkers and identified weak points which we improved over time.”
The ‘Jerk Test’
Once the Simond MT900 Ultralight 50L pack was perfected, it was tested almost to the point of destruction to ensure it would perform in the real world. It was put through the comically named but nonetheless revealing ‘Jerk Test’, which simulates 10,000 sudden drops of a fully-loaded bag in order to test the fabrics and construction.
It was also tested for real on the Pacific Crest Trail in the US, covering around 4240km over five months.
Guaranteed longevity
Like Decathlon's own Forclaz packs, the Simond Ultralight 50L is backed by a 10-year guarantee. This covers all components from the zips to the seams (although it excludes normal product wear and tear), meaning that if yours fails due to a defect, you can claim a repair, replacement or refund.
Verdict
The roll-top style of the Simond MT900 Ultralight 50L may not appeal to every hiker. But if you can live with the quirks, its light weight and excellent comfort may well win you over.
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Osprey Eja Pro 55 £240
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We recently put the latest versions – the Exos Pro and Eja Pro 55 – through their paces and were seriously impressed by how well they manage to combine minimal weight with practical features.
Read our full Osprey Eja Pro 55 review here.
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Read our full Exped Lightning 60 review here.
About the author
Ben Weeks has been with Trail for over 10 years and is our main point of contact for all gear reviews. As well as being a hugely talented writer and photographer, Ben is also a qualified Mountain Leader and Climbing Instructor.
Along with walking, scrambling and wild camping, he loves gnarly Scottish winter routes so is a master at putting cold weather kit through its paces.