MSR GUARDIAN Portable Water Purifier 5044-433

MSR GUARDIAN Portable Water Purifier

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Show Description

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

Show Tech specs
Weight 490g
Ideal for
  • Camping and hiking
  • Backpacking
  • Travel
Filter type

Water can be treated using various types of filters, chemicals or non-chemical purification methods, or a combination. Filters on their own will not remove viruses as they are too small.

Hollow fibre technology
Output 2.5L/min
Dimensions 21 x 12cm
Cartridge life

The life of the filter cartridge is based on the quantity of water you can treat before the cartridge is no longer effective. This does not apply to battery operated or chemical filter systems.

Filter size

A 0.5 micron or smaller filters protozoa and some large bacteria; 0.2 micron or smaller filters smaller bacteria such as campylobacter.

Effective against protozoa

Protozoa are larger than one micron and include cryptosporidium and giardia.

Effective against viruses

Most viruses are in the 0.1 micron size range, but they can be as small as 0.002 microns.

Effective against particulate

Particulate consists of very small bits and pieces such as dirt or bugs.

Effective against bacteria

Bacteria can cause illnesses such as diarrhea and dysentery and are about 1.0 micron in size, although some can be as small as 0.2 microns.

Made in USA