This set contains two Life Straw Go 2-Stage Water Filter Bottles. The Life Straw Go Water Bottle personal water filter has been updated with 2-stage filtration to improve the taste of filtered water and provide even better protection from contamination. In addition to the award-winning Life Straw hollow fiber membrane filter that eliminates bacteria and protozoa, the next-generation Go Bottle incorporates a carbon capsule that reduces bad taste, odor, chlorine and organic chemical matter. The convenient, reusable Life Straw Go personal water filter bottle is ideal for hiking, camping, or traveling to areas with poor water quality, and is a critical addition to any disaster survival kit or bugout bag. Easily to fill by scooping water from any pond, stream, or river, filtration happens while drinking through the mouthpiece. The Life Straw Go filters water down to 0.2 microns and has been rigorously tested to surpass EPA standards for removing E. Coli, Giardia and Cryptosporidium oocysts, and many other waterborne contaminants; removes 99.9999% of waterborne bacteria and 99.9% of waterborne protozoan parasites. When the filter has reached capacity (1,000 liters / 264 gallons) it will stop taking in water. Replacement filters are available for sale separately. For each Life Straw purchased, one child in a developing community receives safe drinking water for an entire school year.