Mountain Equipment Company

MSR GUARDIAN Portable Water Purifier


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Shop with confidence. If it’s not working out, you can return it (consumables, electronics, undergarments and swimwear excluded).
Really. If it's not up to snuff after you use it (a couple times) you can still bring it back. It lasts longer than 30 days, but not forever. We'll be fair about it.


A true game changer that makes almost any questionable water source safe to drink. This purifier means you don't need to carry chemical water treatment, or a UV purifier when you are in virus territory. It removes viruses, bacteria, and protozoa. And it back-flushes itself during normal operation, so it's a lightweight and convenient package for travel and expeditions.

  • Filters 2.5L per minute at 60-80 strokes per minute
  • Hollow fiber filter removing bacteria and protozoa
  • On every stroke, 10% of the water flushes contaminants from the filter back into the source, so no back-flushing or scrubbing cartridges
  • Withstands freezing
  • Drop tested from 6 feet to concrete, as conducted by the MSR lab
  • Includes storage bag and manual
  • Note: the quality of water will significantly affect the filter's life

Tech specs

Ideal for
  • Camping and hiking
  • Backpacking
  • Travel
Hollow fibre technology
Dimensions21 x 12cm
Made inUSA

Reviews (117)

4 out of 5 stars with 117 reviews for MSR GUARDIAN Portable Water Purifier

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