Simply remove the cap and insert into the water, then start to drink the clean filtered water from the top of the straw
Is also be something I think that would go great in a car in case you get stranded in the winter or just about for any reason whatsoever
Sometimes they are camping out in places where there is no fresh water available
It is pretty small and easily fits into a bag pack
This straw will come in handy and I can be sure they are not drinking unsafe water
It'd be great to keep for camping trips, or even hiking