Woder N22-Sur Survival Water Filter Bottle - 22oz. Nalgene Portable Purification Unit - Removes 99.99% C. Parvum Oocysts and E. Coli and Bacterias - USA-Made

I used this just once on a trip abroad - it was very hard to get water out of the bottle and into your mouth. i understand that it has to pass through the filter, but it might have helped if there was a mechanism where you could squeeze the bottle to help push water through the filter.I cannot comment about the purifying features, since the water was not really bad where I was. Did not know what to expect so went over-prepared.

Easy to use and love the BPA free!