The large thermos is functional and keeps its temperature. It is definitely not the highest quality, but for its price, it's okay. The small one is a waste. Its lid doesn't seal properly, resulting in easy water spills, and it has an unpleasant smell that doesn't go away no matter what I tried to wash it with.

Both lids are snap-on and not screw-on, and they are very easy to open. My 15-liter one came with a leak from the faucet, so I unscrewed it from the inside and passed the rubber that it had from the outside and it stopped. I come back after months where I used it a few times, the handle from the big one broke very easily. I do not recommend it, it's better to spend a little more and get a higher quality one.

When it was delivered, the products were not properly packaged. So the 15-liter faucet came broken. In order to avoid the process of exchange, etc., I used the 6-liter faucet in the 15-liter one. (The 6-liter one didn't suit me anyway, I made the purchase solely for the 15-liter one.)