MSR Guardian Gravity.
Gravity-fed hollow-fiber purifier that removes viruses, bacteria, and protozoa without chemicals. The set-it-and-forget-it option for group trips and base camps.
The Verdict.
Gavler Meta-Score
“The group-trip water solution. Gravity-fed purification handles viruses without chemicals, processes 3 liters in 3 minutes hands-free, and self-cleans automatically. Too heavy for solo UL; essential for groups.”
The Gavler Verdict
Precision Engineering
Virus Removal
Hollow-fiber purifier removes viruses, bacteria, and protozoa mechanically — no chemicals or UV needed.
Hands-Free Gravity Flow
Hang and walk away — 3 liters purified in 3 minutes without squeezing or pumping.
Self-Cleaning System
Automatic backflush with every use maintains flow rate without manual maintenance.
Technical Specifications
The Scoreboard
Best group filtration system available. Deducted for weight and bulk that make it impractical for solo ultralight use.
Cast Your Vote
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Best Price Availability.
Prices checked April 2026
Price History
Lowest price in 30 days30-Day Low
$89.95
30-Day High
$89.95
Current
$89.95
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Global Critique
“The Guardian Gravity is the best group water system we've tested — hang it and forget it.”
“Virus removal without chemicals is the Guardian's killer feature for international trips.”
“Self-cleaning hollow fiber that maintains flow rate over time. MSR solved the backflush problem.”
“The right answer for groups of three to six who want virus protection without chemicals — gravity does the work while you set up camp.”
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