MSR Guardian

[amills]

I have no affiliation with MSR, FYI:

Recently bought a MSR Guardian. I know its a little bigger and heavier than most would prefer, but the fact that its a purifier, and is self cleaning sold me. 3 of us hiked the 1st 40 of the AT 2 weeks ago. Right when the Norovirus outbreak started... Cant tell you how glad I was to carry and a little more weight/size... No one got sick. Its also very, very fast. We were about 1L/min to fill. Cant recommend it enough!!

[HooKooDooKu]

Is this the filter you're talking about? (https://www.rei.com/product/891193/msr-guardian-purifier)

WOW!... what a price tag on that thing.
But then again, there is no other filter that I know of that physically removes viruses, can withstand freezing, and doesn't require back flushing.