This is the bottle I have and have used extensively in Ecuador. It is easy to use and carry. I like the fact that it is also viralcidal. The only problem I had was at the X-ray machine at the airport, the filter portion itself, shows up as a very dense item, which the screeners then check to make sure it is not one of the prohibited items.

ORINOCO 26oz. BOTTLE
http://shopping.wideworks.net/mivastore/...ct_Code=orinoco

I actually have two, one for myself the other for my wife/daughter, whoever is traveling with me. The first one I bought locally from Hudson Bay Outfitters, the other I got much cheaper on the net from one of the on-line outdoor gear companies. There is also a larger version as well. Hope this helps. Pete