the freshbuzz product is easy to use and handy; it can be packed easily with least weight or space.
It is a good tool to use abroad, you need to raise the quality of the nozzle part as of leacking. I have another idea to be studied; just make a bottle closer in addition to the nozzle to avoid leacking. They have a good customer service and very responsive. Overall, the product is very useful and should be with every traveller.