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Sawyer Select S1

rated 4.0 of 5 stars
photo: Sawyer Select S1 bottle/inline water filter

The Sawyer Select series is a new line of purifiers/filters that offers a variety of contaminant removal, depending on one’s needs. All three models remove chemicals to .5 ppb (parts per billion), and pesticides to .01 ppb. The Sawyer Micro Squeeze filter can be used without the purifier to a .1 Micron level.


  • Micro Squeeze filter has better flow rate than Squeeze and Mini
  • Filter can be used by itself
  • Complete kit provides ease of mind


  • System is bulky/cumbersome
  • Weight
  • Purifier bottle fills slowly
  • Difficult to dry

Sawyer’s new Select Series is a kit that will provide potable water from virtually any freshwater source. Although this kit can be easily used in backcountry setting, it is primarily designed for front-country use.



  • Volume Capacity: 20oz
  • Number of Uses: 1600
  • Filter Rating: .1 Micron
  • Chemical Reduction: .5 ppb
  • Pesticide Reduction: .01 ppb
  • Included Cleaning Plunger
  • Included Cleaning Coupling

Sawyer's lab tests can be found here:

IMG_0409.jpgSize comparison to a 32oz Nalgene bottle

IMG_0418.jpgSize comparison to a sticker-customized Sawyer Mini

Filling the reservoir was found to be a chore, due to very slow absorption from the foam, as well as the straining disc at the top of the reservoir. 

IMG_0410.jpgA closeup under the hood

Once the reservoir is filled, Sawyer directs to squeeze the bottle in an alternating motion for about ten seconds so the water is forced through the inner foam membrane. Once the filter is threaded, simply squeezing the flexible reservoir forces the water through the hollow fiber core. 

IMG_0411.jpgCloseup image of the foam inside the purifier

Sawyer’s proprietary treated foam inner prevents any growth inside the reservoir, but never truly dries out. Sawyer states that the reservoir never needs to be dried. Per Sawyer, there is no available information to indicate that the filter will be harmed if frozen, however replacement is recommended in these circumstances. This applies only to the hollow fiber filter, not the foam block, or silicone bottle. 

Per Sawyer: "Completely drying out the the Select Bottle is not necessary. The absorption filtration technology within the foam is designed to both filter water as well as prevent growth. If you do dry it out and mold grows on the unprotected walls of the bottle, fill the bottle with water and continuously squeeze and release for approximately 3 minutes or until the mold is gone."


Although easy to use, the reservoir is not an ideal lightweight backpacking option, unless chemicals and pesticides are suspected to be a contaminant. Otherwise, the Select Series is an efficient, quick system to use. The purifier system without water weighs in at 14.2oz, while the Micro Squeeze weighs 2.2oz by itself.


Hopefully Sawyer plans on marketing the Micro Squeeze as a separate filter, as its flow rate surpasses the Mini, as well the Squeeze models.

IMG_0412.jpgThe svelte Sawyer Micro Squeeze

IMG_0413.jpgTop of filter

IMG_0415.jpgBottom of filter

The construction and durability of the Select S1 is of similar quality to previous Sawyer filters. Over-tightening is a common concern for Sawyer filters, which can result in leaking. This isn’t considered a fault, however care must be taken in order to prevent contaminated water from running off to the potable outlet.


The outer silicone material of the reservoir can get tacky at times, and also retain dirt and grime. Although very grippy, it can be difficult at times to get the reservoir in and out of water bottle pockets.

Conditions:  This purifier/filter system has been tested from autumn to late winter 2017-2018 in the Mid-Atlantic region of the USA. It has been on several day hikes, and several overnight backpacking trips in the region. Temperature ranges during testing was between 15°F-70°F.


Conclusion: The Sawyer Select S1 filter/purifier is a great all-around system for those that need a broad-spectrum method to treat fresh water, regardless of location. Whether on the trail, or vacation, Sawyer Select purifiers will have you covered!

Many thanks to the people out at Sawyer for the opportunity to test the Select S1 Purifier system for the Trailspace Gear Review Corps.

IMG_2233.jpgSeeking shelter on the Appalachian Trail 

Source: received for testing via the Trailspace Review Corps (Sample provided by Sawyer for testing and review)

Great product. Easy to use and serves as a lightweight purification method.


  • Lightweight
  • Effective
  • Easy to use


  • Individual system

Wow, what an easy to use and effective lightweight water purification method.

Great for the individual for backpacking and hiking.

Source: received it as a personal gift

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Price Historic Range: $15.00-$59.95
Weight 10 oz
Volume 20 oz
Removes Bacteria, Protozoa, Chemicals, Pesticides
Number of Uses 1,600
Product Details from Sawyer »

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