I started using it in the summer at the beach with the prospect of using it in the winter for hot tea and coffee. When I put cappuccino inside, I noticed the time and moment. There are residues (from the foam) that I cannot clean, no matter what I have tried, in the folds of the lid as it twists. It is an expensive thermos, with good construction, waterproof, I just throw it in the bag as it is, but in terms of cleanliness it is difficult with the twisting lid, so I can't enjoy it as much as I initially expected due to the cost.