Gear Review: Sawyer Select Filter and Purifier

Sawyer Select Filter and Purifier

S1 (Filter)


  • Bacteria
  • Protozoa
  • Chemicals
  • Pesticides

Uses: 1600

Cost: $59.99

S2 (Purifier)


  • Bacteria
  • Protozoa
  • Chemicals
  • Pesticides
  • Viruses

Uses: 800

Cost: $79.99

S3 (Purifier)


  • Bacteria
  • Protozoa
  • Chemicals
  • Pesticides
  • Viruses
  • Heavy Metals

Uses: 400

Cost: $89.99

Specs for All:

  • 10oz field weight
  • Length: 3in
  • Width: 8.5in
  • Height: 14in
  • 20oz of water output
  • 10s to treat water

Sawyer created the S1, S2, and S3 as a way to accommodate different water purification needs.

The guide on their website is helpful in figuring out the differences between each and what you might use them for.

The S1 is meant for someone looking to guard against the more basic—but still nasty—bacteria and pesticides. The example they give is someone hiking in Texas and worrying about pesticides from agricultural runoff. The S2 is more meant for roughing it abroad, where you run the risk of encountering viruses. The examples they give for the S3 are related to intense scenarios like natural disasters or exposure to industrial pollutants. For the average thru-hiker, thinking of trails like the AT and PCT, the S2 is what I would recommend.

I tested these filters on a hike around Trillium Lake in Clackamas County, Oregon. It was an overcast day that was sprinkling rain and just getting into the colder temperatures, around 35.

How It Works

To use a Sawyer Select Filter, unscrew the filter from the bottle. Fill it up from a water source, all the way to the line that says “Max Fill.” Screw the filter back onto the bottle, then squeeze the bottle’s foam core in an alternating motion for ten seconds. You’re good to go! Drink straight from the bottle or squeeze it into another container.


The Sawyer Select Purifier is a very compact system in the sense that there are only two parts: the Micro Squeeze and the foam filter or purifier. The Micro Squeeze filter easily screws onto the foam filter/ purifier and once it’s filled up, you’re good to go. You don’t have to wonder if your filter will fit onto your water bottle since it’s all in one.

For a day hike, it was nice knowing that all I had to do was fill up three of these (one for me, one for a friend, and one for my dog friend) and we weren’t going to need to bring anything extra to store the water we filtered.

As a very tactile person, I found the experience of actually squeezing the foam filter really fun! It only took ten seconds of my time and since we were near an ample water source, the bottles filled up quickly.

At first, it took a lot of squeezing to get the water flow at a good pace, but I attributed that to it it’s first time being used. After getting it going, the flow rate felt normal. I also appreciated how easy and fast it was to dispense the water out into another container, in our case, a dog bowl. The water also tasted great!

The casing around the foam is malleable but it feels thick which adds a level of comfort when wondering how much wear and tear these filters can take.


The Micro Squeeze plus filter/ purifier also makes this setup very long, about 14in. It felt a little unwieldy to drink straight from the bottle because of its length. You also have to work a little harder to completely empty the bottle. With a standard water bottle or even a Sawyer pouch, you either don’t have to squeeze or it’s easier to squeeze those last drops out. The extra weight from the foam core and added length didn’t make sense to me for long-distance backpacking.

Hiking around a lake made for easy refilling but I wondered how this product would fair in a shallower water source. The filter/ purifier is somewhat flexible, but it seems like it would be a real challenge to work with something that long in a variable water source without a cup or a funnel.


Thinking as a long distance backpacker, this is definitely not the lightest or most compact option on the market from Sawyer. These products feel much more suited to day hiking or traveling abroad than long-distance backpacking. Coming from a brand like Sawyer, I believe that the product is well made and that the price is accurate, especially if you have concerns that are more suited to the S3’s specialties.


Find out more about these new filters here

Shop the Sawyer Select Here

Disclosure: These products were donated for purpose of review


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