I also use TAI℃ titanium thermos cup now. In addition to those you mentioned, there are titanium cups, which are safe and healthy, and no harmful heavy metals are dissolved during the storage of drinks. The most important TAI℃ titanium thermos cup is made of pure titanium, which is resistant to strong acid and alkali, tea, coffee and juice drinks. Any kind of beverage can be safely filled without heavy metal precipitation, which not only has heat preservation effect, but also can meet various needs of human body.