Guardian Military-Grade Water Purifier

Score: 9.0/10 | The MSR Guardian represents the pinnacle of portable water purification. NSF P248 certification means it meets the U.S. military standard - the strictest in the world. Self-cleaning technology solves the clogging issues that plague other pump purifiers. Premium price for premium capability.

The Guardian is the first purifier to meet NSF Protocol P248, developed for the U.S. military. This exceeds all consumer standards:

• Viruses: 99.99% (4-log)
• Bacteria: 99.9999% (6-log)
• Protozoa: 99.9% (3-log)

Unlike UV or chemical treatment, the Guardian uses purely physical purification. No taste impact, no waiting, no consumable chemicals.

Designed to purify from puddles, livestock ponds, and highly turbid sources where other filters fail.

The Guardian automatically backflushes with each pump stroke. This prevents the clogging that renders most pump filters unusable in dirty water.

The fastest pump purifier available. Fills a 1-liter bottle in 24 seconds.

Approximately 10,000 liters before cartridge replacement. For typical expedition use, this is years of purification.

Certified to work in temperatures from 32°F to 120°F. No batteries, no UV, no chemicals to fail.

The premium price reflects military-grade capability. This is expedition equipment, not casual camping gear.

At 10,000 liters, cartridge cost per liter is reasonable for serious users.

Heavier than filter bottles but significantly lighter than carrying equivalent water volume.

The MSR Guardian is for serious expeditions and worst-case water scenarios. If you need to drink from a livestock pond, this is your tool. For casual camping, the Sawyer Mini or Grayl GeoPress is more practical.

Score: 9.0/10 | The MSR Guardian represents the pinnacle of portable water purification. NSF P248 certification means it meets the U.S. military standard - the strictest in the world. Self-cleaning technology solves the clogging issues that plague other pump purifiers. Premium price for premium capability.

The Guardian is the first purifier to meet NSF Protocol P248, developed for the U.S. military. This exceeds all consumer standards:

• Viruses: 99.99% (4-log)
• Bacteria: 99.9999% (6-log)
• Protozoa: 99.9% (3-log)

Unlike UV or chemical treatment, the Guardian uses purely physical purification. No taste impact, no waiting, no consumable chemicals.

Designed to purify from puddles, livestock ponds, and highly turbid sources where other filters fail.

The Guardian automatically backflushes with each pump stroke. This prevents the clogging that renders most pump filters unusable in dirty water.

The fastest pump purifier available. Fills a 1-liter bottle in 24 seconds.

Approximately 10,000 liters before cartridge replacement. For typical expedition use, this is years of purification.

Certified to work in temperatures from 32°F to 120°F. No batteries, no UV, no chemicals to fail.

The premium price reflects military-grade capability. This is expedition equipment, not casual camping gear.

At 10,000 liters, cartridge cost per liter is reasonable for serious users.

Heavier than filter bottles but significantly lighter than carrying equivalent water volume.

The MSR Guardian is for serious expeditions and worst-case water scenarios. If you need to drink from a livestock pond, this is your tool. For casual camping, the Sawyer Mini or Grayl GeoPress is more practical.