MSR Guardian Gravity Purifier

Shipping restrictions apply.

Members get an estimated $30.00 (10%) back on this item as a part of your annual .

Members get an estimated $30.00 (10%) back on this item.
To buy,  sign in as an REI Co-op Member or join now.

Drink water anywhere in the world—from local backcountry to remote locales—with the MSR Guardian Gravity purifier. Hang it while you go about your tasks at the hostel, basecamp or campsite.


  • Meets NSF protocol P248 military testing standard—removes viruses (99.99%), bacteria (99.9999%), protozoa (99.9%), sediment & microplastics from "worst-case" water conditions
  • Easy to fill at sinks and streams alike, with a 10-liter reservoir to support the daily water needs of multiple people for drinking, cooking and hygiene
  • 2-stage purifier includes activated carbon to reduce chemicals and unpleasant tastes and odors
  • Cartridge creates a high-flow, virus-stopping gravity system—up to 1 liter in 2 minutes
  • No backflushing required to clean—simply opening the purge hose flushes the system to clean it and maintain flow
  • Rugged, military-grade construction is engineered for travel
  • Compact system fits easily in carry-on luggage and smaller packs

Made in USA.

View all MSR Gravity Water Purifiers

Technical Specs

Best Use


Filter Type


Filter Medium

Advanced hollow fibers


Protozoa, Bacteria And Viruses

Pump Force

Not applicable

Pump Strokes per Liter

Not applicable


1 liters

Housing Material


BPA Free


Field Cleanable



12 x 4 inches


1 lb. 2.7 oz.

33 reviews with an average rating of 4.2 out of 5 stars

Loading Reviews...

Questions & Answers

Loading Questions...