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MSR Guardian Water Purifier

MSR Guardian Water Purifier
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Nothing is safer or easier to use for purifying the most demanding backcountry water sources than the Guardian purifier. Originally designed for military squads, it brings this highly advanced technology to global travelers, backcountry users, and those stocking emergency kits. Fast and easy to use, this pump purifier offers the added viral protection you need when traveling in developing nations and popular wilderness areas. Its advanced hollow fiber filter offers the most reliable way to purify even filthy water conditions. Add its long-lasting performance and revolutionary self-cleaning ease, and this may be the only treatment device you’ll ever need.

  • Ultimate Protection: Meets NSF protocol P248, testing standard used by U.S. military, for removal of viruses, bacteria, protozoa, and sediment from “worst-case” water conditions.
  • Fast & Easy: Pumps a rapid 2.5 liters per minute, offering added viral protection without the need for chemicals, bulbs, batteries, or waiting.
  • Self-Cleaning: Pump self-cleans on every stroke, providing consistently fast flow rates with zero hassle—no backflushing or filter-scrubbing ever required.
  • Long-Lasting: Leading-edge hollow fiber cartridge treats up to 10,000+ liters.
  • Extremely Durable: Engineered to withstand heavy use, freezing, drops*, and harsh environments.
Color Smoke Weight (Standard) 1 lbs 1 oz
Weight (Metric) 0.49 kg Width (Standard) 3 in
Length (Standard) 8.25 in Height (Standard) 4.5 in
Effective against bacteria Yes Effective against particulate Yes
Effective against protozoa Yes Effective against viruses Yes
Filter media Advanced Hollow Fiber Filter pore size (microns) 0.02
Flow (L/min) 2.5 liters per min Cartridge life 10,000+ liters
Field cleanable Self-Cleaning Field maintainable Yes
Water Bottle Adapter Yes Cartridge replacement indicator Yes
Material(s) Hollow Fiber Country of Origin Made in the U.S.A. of U.S. and Imported Materials


Behind the Scenes: MSR Water Research Lab

Part Numbers

040818023709 WAT318236250