SteriPEN - SteriPEN.com
SteriPEN® products are easy to use. Simply snap the topper to the bottle, activate your SteriPEN® JourneyLCD or Classic Water Purifier and insert it into your water bottle. Then, flip the bottle upside down and agitate water until purification is complete.

SteriPEN® uses ultraviolet (UV) light to destroy the DNA of disease-causing bacteria, viruses and parasitic protozoa. Without DNA these microorganisms, even Giardia and Cryptosporidium, can't make you sick. And because the SteriPEN uses light instead of chemicals to purify, water doesn't have an unpleasant chemically taste or odor.
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