Therm-a-Rest® - Sleeping Pads, Bags & Outdoor Comfort

Guardian™ Gravity Purifier

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$216.97 $309.95 In stock

The MSR Guardian™ Gravity Purifier delivers state-of-the-art virus protection in an easy, high-volume gravity system, making it a reliable choice for backcountry water treatment.

  • Gravity-powered design filters large volumes of water with minimal effort.
  • Advanced purification technology targets viruses, bacteria, and protozoa.
  • High-volume capacity is ideal for group trips or extended expeditions.
  • Simple setup and operation—no pumping required.
  • Durable construction built for rugged outdoor use.
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Express Shipping · United States: $3.99

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United States · Return window (days after delivery): 30. Return method: By mail. Return postage: Seller pays.

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Customer Reviews (4.8 / 5 · 5 reviews)

Penelope ★★★★★

I’m a slow hiker so the gravity-fed flow is perfect—set it up, filter a liter while I snack, and it’s ready to pack out. Viruses being covered gives me real peace of mind for those questionable alpine pools. No pumping or squeezing, just steady water.

Owen ★★★★★

Took this on a week-long trip and the gravity flow rate is genuinely impressive—I filtered two liters in a couple of minutes without pumping. The virus protection gives me real peace of mind for streams I used to avoid. It's bulkier than my old squeeze filter, but worth the space for the speed and s

Christopher S. ★★★★★

Set it up at camp and let gravity do the work while I prepped dinner — by the time the pasta was done I had four liters of clean water ready. The flow rate is genuinely fast for a gravity system, and the fact it handles viruses without any pumping or chemicals is a huge peace of mind.