"Best, smartest purchase I've made in some time"
(new york, ny United States)
This is not an exaggeration: the first time I used this when flying, FOUR people I encountered on the trip stopped to ask me how this worked and where I got it (United Club bartender, two United Club patrons, one flight attendant in the air). I'm a travel accessory junkie, and this is the best, smartest product I've bought in quite some time. Not only do I save money on airport bottles of water, but I drink more water as well. And chances are that your airport has filling stations at water fountains - they're there if you keep your eyes open. I bought several of these for holiday gifts for friends who travel.
Highly, highly recommend!