The FLOWTEA is made of borosilicate glass. It is one of the hardest types of glass there is. Nevertheless, it is glass, which is of course fragile. Even the neoprene cover that comes with it is only a limited protection.
The handle on the lid of the FLOWTEA and also the double wall are suitable for using it on the go. However, those who are very agile on the road, who sometimes handle their bottle a little more carelessly, who want to stow it in the drink holder of the bike, etc., should take a look at our LEEZA thermal bottle.
More about the glass used can be found in our blog: What is borosilicate glass?