I think they're technically thermoses but essentially just a well insulated water bottle. In the same price range as a kleen kanteen and zojirushi has a good reputation for making quality products so with proper care should be a good BIFL purchase.

I got blocked by the automoderator for posting an Amazon link (not affiliated) so I'm just gonna mention that I searched zojirushi bottle and found some that are specifically water bottles (one touch open) and not the thermos style. Tbh I didn't even know they made those!