Unfortunately, I did not find it user-friendly. Firstly, there were no instructions for use in the packaging, resulting in me having to find a video on YouTube for how to use the item. Secondly, the bag is very soft, which means it spreads out inside the backpack, taking up a lot of space. Thirdly, it requires caution because if it is pressed, water leaks out. It must always be kept in an upright position.

Classic hydration bladder with a flexible long tube measuring almost 1.10 m from the point where it connects to the bladder to the mouthpiece. It does what it promises, good build quality. It has an on/off system (shown in the photo) for extra safety. Overall, for €15 it’s a very good deal considering it’s 3L. In the photos, I show its application on a Salomon hydration vest; the bladder is a bit larger than it should be for this vest, but it certainly doesn’t make it useless.

EDIT 18/08/2024
The bladder along with the vest have already been used for trail running and hiking. A couple of words that I couldn’t find anywhere, so I would like someone who wants to buy it to know if it’s their first purchase of similar equipment (as it was for me).

-First (for running). The bladder, whether 2 liters or 3 liters, moves during exercise. I will say that the 3-liter one takes up more space inside the vest due to its larger volume, essentially "getting wedged," so compared to the 2-liter, it moves less. However, it’s something you get used to.
-Second. After you drink, a quantity of water is stored inside the straw, resulting in the next time you drink, the first 2-3 sips being much warmer than the subsequent ones that come directly from the bladder. On a route that you might take and doesn’t have sources or generally supply from somewhere, keep in mind that a quantity of water will either go to waste or won’t be as pleasant to drink.
-Third. In the first uses of the bladder, the water will have a plastic taste which will diminish over time. Give it some time, and after a while, the taste won’t be like in the first uses.
-Fourth. If you want to have electrolytes on hand in solution, it’s better to use either a 500-gram bladder or a thermos or a 500-gram plastic bottle, generally something other than the bladder. The bladder will absorb the smell of the liquid after a while and will take time to return to a neutral state.

I hope I helped!

Although the water bottle kept the water at a good temperature throughout the day and had a convenient hose and nozzle for drinking during mountain climbing, it leaked water from somewhere, resulting in everything in the hiking bag getting wet. I tried it three times on different hikes and unfortunately, all three times it lost a significant amount of water and soaked everything. Maybe this specific water bottle was defective.