The Katadyn Hiker Pro Water Filter has the improvement of a second filter that wraps around the internal filter cartridge making the cartridge last longer. Great reviews on this hiking filter. Great choice for a long term camping trip or thru-hiking the triple crown.
This is the model water filter I personally carry in my backpack.
The Katadyn Combi – Water Filter For Hiking. The Combi is a state of the art water filter that is a must have for the lightweight hiker. Keep this at the ready in your bug out bag or backpack. This is a top rate hiking water filter. I would buy this water filter, If I didn’t already have the MSR SweetWater.
The filters removes organisms, bacteria, and other particles. Includes a cleaning brush. And if you are somewhere that you are worrying about viruses, This also comes with a solution that kills viruses. I carried this with me while hiking on the Appalachian Trail and loved it.