I really like the Vapur collapsible and reusable water bottle made from BPA free plastic. It can be folded flat when empty. You can fill it up with water and freeze it. I would buy this and use it when I travel specially on domestic flights in the US. I’d put it in my bag empty and after passing security check I can just fill it up with water from the drinking fountain. That way I don’t have to shell out $3 for a small bottle of water. Vapur comes in 16 oz. size only and costs $8.95. Too bad it’s out of stock in their online store.
Unlike rigid water bottles, Vapur is completely collapsible. This means it goes more places and fits in tighter spaces than any other bottle. Whether you are hiking the trails, passing through airport security or visiting the museum with your family, Vapur makes water infinitely portable.