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Forclaz Men's MT900 50+10 L Ultralight Backpacking Pack

Regular price: $189.00 Regular price:

Thanks to the design choices, FORCLAZ reduced the weight of this bag to just 2.9 lbs without compromising on durability. The bag can be tailored to your needs thanks to the multi-purpose straps.

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Sale price: $189.00 Regular price:

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About this item:

  • This backpack is made for multiple days hiking or trekking in autonomy. You can carry everything you need to camp, drink and eat on your back with comfort.
  • The MT900 ULTRALIGHT only weighs 2.9 lbs and can contain a total volume of 45 liters which we recommend for a trip under 2 weeks long. The top of the bag is adjustable and can hold an extra 10 liters of volume.
  • This backpack has plenty of features if you are looking for a lightweight technical option at a great price: AIR concept back ventilation, rain cover, water bottle holder, hiking poles holder, 7 pockets and a compartment for a water bladder for easy hydration.
  • The AIR concept: in order for your back to dry faster, we added a mesh on top of a ventilated structure. Ideal for long and sweaty day hikes from one camp to another !
  • This is a men's backpack: This bag has been conceived for a masculine morphology (torso and hips). We recommend to stick to your gender when you choose a bag for comfort purposes when carrying it on your back.
  • 10-year warranty: the fabric of the bag is ultra resistant and Decathlon is proud to offer this warranty for any defect that could appear in the next 10 years.
Model: 8642599

Product Videos

Product Features

Forclaz Men's MT900 50+10 L Ultralight Backpacking Pack | FORCLAZ designed this ultralight & robust bag for demanding users looking for performance. Ideal for completing 2 stages of a long-distance hiking trail in 1 day.

Thanks to the design choices, FORCLAZ reduced the weight of this bag to just 2.9 lbs without compromising on durability. The bag can be tailored to your needs thanks to the multi-purpose straps.

A photo of the Forclaz Men's MT900 50+10 L Ultralight Backpacking Pack in use

Carrying comfort

Carrying up to 26.5 lbs, suitable for men. Ventilated back, adjustable height

Multiple compartments

Full height access to the central section, 7 pockets (cent. sect: 3, lid: 2, belt: 2


Pole holder, rain cover, side pockets which can be accessed when walking

Abrasion resistant

Main fabric in 100D RS polyamide, reinforced bag bottom (210D RS)


Reinforced frame with mesh reducing pressure and letting the back breathe.

Easy hydration

Internal compartment for a water bladder (not included)


2.9 lbs (1.3 kg). The empty weight indicated is that of our benchmark sample

Product Lifestyle Image Gallery

Image Gallery

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Product Customer Reviews

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Tested on the GR…

Tested on the GR 20, this bag is very light, very pleasant to carry and is quite durable. The only downside is that the side pockets do not close (which surely contributes to the lightness of the bag)

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OK OVERALL, good product

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Decathlon's best in-house backpack

A really decent backpack that can withstand comparison with renowned competition. For me, the design of the back is a bit of a disadvantage - the mesh and the worse possibility of packing the backpack to the optimal center of gravity - but this is a characteristic feature that is not completely satisfactory for me even with other brands of backpacks. Small fault with the surface of the shoulder straps - it is not very pleasant and it scratches a lot on the bare body - completely useless on a sweatshirt or jacket. The only major complaint is directed at the length of the loincloth - it is terribly long and the effort to be universal is detrimental (and limiting) here - it cannot be tightened well. Overall, the backpack exceeded my expectations, packability, carrying comfort; the front zipper works better than expected. The other things I would criticize are obvious at first glance and there is no backpack that will please everyone :-) . I can recommend it to everyone who is looking for a decent all-purpose backpack in this size in a price/performance ratio, with a reasonable weight.

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Lightweight but robust multifunctional comfortable trekking backpack

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My first real lightweight backpack!

This is my first real hiking backpack! I load it between 7 and 8.5kg without water. Pros: Nice. Light. Large capacity. Easy and convenient adjustable carrying height. Well-designed frame, effective anti-perspiration net. (We will always sweat but the air circulates). Efficient and wide ventral tightening, good support but it lacks padding and therefore comfort on long outings! Convenient belt pockets. Modular, possibility of gaining 100gr by removing the upper pocket, that's what I did. The -: All the straps are way too long, I shortened them. Despite several different settings, in just two days of hiking the main carrying straps end up irritating me around the collarbones, I'm rather thin and bony but this is very unpleasant when carrying! This happens on every one of my mountain hikes. Is this the price to pay for having a light bag??? These straps should have much better padding even if it means taking on a little weight!!! The side pockets are not practical, I'm fine with them but it's easy to lose what's inside, their lacing system is not reliable and not practical... The bag does not fit straight once placed on the ground... In my opinion, the load should not exceed 10kg, including the bag, otherwise you will experience great discomfort! So I made the choice to carry my 1.5l of water in a banana bag so as not to weigh down the bag. I do not know if I will recommend the purchase of this bag, despite its many faults it suits me but there must be much better among the competition! Definitely more expensive too...

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extremely fragile side pocket

After 3 days of hiking, a side pocket was no longer usable. The rope came out, and I was unable to find a possible repair

It was a comfortable stay in a tent.

The other day, I went to Mt. Kisokomagatake for the first time in my life. Thanks to this rucksack, I was able to climb comfortably! It's light and doesn't feel too heavy for its capacity, and it's very easy to use because you can adjust the best position according to your physique! The structure makes it easy to access the luggage compartment, so it was very helpful when cleaning up. The side can hold three 500ml plastic bottles, making it easy to take.

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Mediocre quality

Hello, I bought this bag on July 6, 2022, since then I made two big ones in the summer of 2022 and a first one at the end of July 2023. During this hike, a crimping of the cable used to hold the side pockets broke! So I went to a Decathlon store to explain the problem. Unfortunately, the disastrous after-sales service! I find it abnormal, and even scandalous, that the only answer I got was: "The bag is over a year old, so it is no longer under warranty. Moreover, it is probably not repairable! " Already ATTENTION, the guarantee is noted 2 years on the site but it does not take into account this type of problem, which strongly resembles a manufacturing defect! Then, these are bags that are mainly used for big hikes, so it's mainly summer. The warranty is therefore only 2 months! So I find myself with a €130 bag that only served me for one summer, and which is good to throw away! I have to leave next weekend, so I have no choice but to buy a new one, which naturally won't be from Decathlon!


I'm a little stunned by the reception I just had for a return of this bag. I am not satisfied with the experience I had on the first hike with this bag. Very bulky bag, a hard point in the back despite all the adjustments tried, and a start of strap noise that is not very pleasant. The bag is new, with no signs of wear. I used it for 4 hours. I was told that it was not refundable but that he could take it back for 70€…. I still do not understand. I have a long list of purchases at decathlon, and I am refused this refund. In short, I am not very happy with this observation.

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A little problem with the…

Small problem with the hooks to carry a tent under the bag. One of the two showed signs of weakness after only two days of hiking, it had to be straightened with a stone and then be very careful the following days...

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Excellent hiking bag,…

Excellent hiking bag, light and very practical.

It squeaks...

The bag is very functional with its full length zip and its accessible and generous side pockets. It is also very comfortable. On the other hand, after 3 weeks I have to face the facts, there seems to be a big design problem, and this has 2 levels: - the unbearable creaking of the frame in contact with the bag, all the more noticeable when descending. It may seem innocuous, but the more the time pinches, the less you support it... - the system of tightening the straps at the bottom of the bag which does not block anything (you can do the test by pulling on it,). Really reassuring if we have the tent fixed... If no technical solution can be provided for the squeaking, I will have to get it reimbursed and look elsewhere. And that's really a shame.

Very disappointed

I am disappointed with this bag that I was offered. The positive points: _You can still put a lot of things in it _ The mesh and fabric seem resistant on the outside _ you can put a water bladder _ the side pockets (in a slightly mesh format) suit me The negative points _First of all, the surroundings of the bag hurt. There is no way to make the bag rest a little on the hips. _ inside, the mesh is so tight that it crumbles, and that without even using it _ good comfort that can be understood given the weight _ it makes noise (but I'm not as bothered as other comments. _ it lacks carabiner attachments or net/lace to trap things I went to do the TMB for 7 days with it. believe me it's money unfortunately thrown away … it's the first time that I grade an article so badly.

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Silence: 2 stars

Bought because of its lightness to travel the GR10 between June and July. Here is my feedback after 970km and 5 weeks of use. Light and resistant, no tearing to deplore, the yellow straps with aluminum buckle and fastening with very practical lark's head knots. The side pockets are to be reserved for bulky objects as they are open on one side. They are solid and the elastic is adjustable. On the other hand the plastic hooks seem fragile to me and I almost lost one which miraculously remained at the bottom of the pocket. They accommodated my water pocket, which I prefer outside the bag, and a 1l water bottle. The tent can also be accommodated there if necessary. The central pocket is the only one that is closed on both sides, we put a lot of mess in it and served as a hair dryer. The central zipper is practical but seems to me to be a weak point in the long term. Not easy to reseal the full bag. the 10-year warranty is reassuring. On the comfort side, I had shoulder pain for the first few days, then the body adapted to the fineness of the padding of the straps (1.3 kg involves certain arbitrations) The waist belt is not tight enough because of the size of the pockets for my size (38) but I got used to it. On the other hand, I suffered from noise pollution which seems to me to come from the straps of the bag height adjustment. I even made audio recordings. It only got worse over the crossing and especially on the descent. No adjustment could overcome it. That's why I don't want to keep this bag and can't recommend it.
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Additional Product Information


Main fabric: 100.0% Polyamide ; Lining: 100.0% Polyamide ; Yoke: 100.0% Polyamide ; Webbing: 100.0% Polypropylene ; Bag cover: 100.0% Polyester ; Coating: 100.0% Polyurethane


Height: 25.6” I Width:13.8” I Depth: 13.8”


2.9 lbs (1.3 kg) All inclusive. Weight of the removable rain cover 3.5 oz (100 g).Weight of the removable lid 3.5 oz (100 g).i.e. 2.42 lbs (1.1 kg) in simple mode!

Air design

Inspired by its sister, the MT500 AIR, this bag replicates many of the features of its ventilated back structure with a mesh fabric so that the back can breathe more and dry quickly.


50 L volume +10 L extension. The volume of each backpack is measured using a standardised method. we use small balls to fill the main compartment as well as each pocket. The balls are then emptied into a graduated container in order to determine the equivalent volume in litres, with a margin of error of just a few %.

How to pack a backpack?

Put your bedding at the bottom. Put heavy gear (tent, camp stove, food) near your back. Store your clothing around it. A groundsheet or tent can be placed under the flap or under the bag if there isn't room inside. Keep your waterproof jacket and fleece to hand. Place small items for daily use (sun cream, map, glasses etc.) in the pockets. The water bladder can be placed in the compartment provided down the back.

How to use the multi-use straps?

The new MT500 AIR and MT900 UL series of trekking backpacks have two straps with open aluminium buckles (on the lower part of the bag). These straps let you hook on a tent or mattress under the bag or on the barrel. If not in use, these straps can be stored (by pushing them inside) in the hidden pocket intended for this or detached and used elsewhere with the lark's head knot buckle.

Complementary accessories

To make your MT900 UL bag easier to use, check out our storage accessories, repair buckles or hanging straps on our website.

Recommended carry weight

According to the project for which this backpack was designed, we recommend you don’t load it above 12 kg. Then you can benefit from all its features. Moreover, it’s not recommended to carry a load greater than 20-25% of your own weight and put too much pressure on your back.


Main fabric in 100D RS polyamide (ripstop = additional resistance to tearing), reinforced bag bottom (210D RS)

Product testing

All our backpacks are field-tested by users who represent the target market in conditions identical to those found in typical use. In particular, our Test Missions bring together the product manager with people who are not affiliated with DECATHLON to test, improve and validate the products. This particular model was tested over a five-week period by trekkers in the Canaries, Pyrenees and the Mont-Blanc mountain range.

Storage instructions

Store your bag in a dry, ventilated place away from direct light.



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