Aquaway Pen – Portable Personal Water Filter – Advanced 3-stage Filtration Process, 2 Back-up Replaceable Pre-filters Included 3-stage filtration process with tested 0.1 micron pore size removes minimum 99.9% of waterborne protozoan parasites and minimum 99.9999% of waterborne bacteria 2 back-up replaceable pre-filters to extend its lifespan. The pre-filter blocks particulate matter before it gets to the hollow fiber membrane Weighing less than one ounce and only 5.4 inches long, the pen-like design makes it easy and […]