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This recorder-sized miracle protects against bacteria (including E.coli and Salmonella) and parasites (like Giardia and Cryptosporidium) and filters out debris. Using it is simple: pop off the caps, stick the bottom end into some (preferably moving) water or a container you’ve filled,

It works by using clever UV-C light inside the lid to zap bacteria like E. coli and keep the inside fresh and stink-free. Just tap the button and in about 60 seconds, you’ve got clean water and a bottle that basically cleans itself, so you can spend less time scrubbing and more time staying hydrated.