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Sawyer 4L Water Filtration System Review

This product has a lot of potential as a group and individual filtration system, but falls short as of now
Sawyer 4L Water Filtration System
Photo: Sawyer
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Price:  $150 List
Pros:  Two water storage containers, turns into hydration bladder
Cons:  Missing a mouthpiece, heavy, dispensing cap doesn't fit properly
Manufacturer:   Sawyer
By Jessica Haist ⋅ Review Editor  ⋅  Aug 10, 2016
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  • Reliability - 25% 8
  • Weight - 20% 4
  • Treatment Capacity - 20% 9
  • Speed - 15% 9
  • Ease of Use - 20% 8

Our Verdict

Sawyer no longer makes the 4L Water Filtration System.

We've loved the Sawyer products we have tested so far like the Sawyer Mini. When we saw that they came out with their own version of a gravity filter, we were excited to try it out. Unfortunately, we were a bit disappointed with the Sawyer Water Filtration System when we field tested it and think it is still missing a few essential components to make it truly complete. It feels to us more like we tested a prototype than a complete market ready product. Read on to find out more.

Our Analysis and Test Results

We think the Sawyer 4L has a lot of potential to be a great gravity and hydration system combination, because it is fast and versatile. We think Sawyer needs to make a few adjustments to their product before it wins any of our awards.

Performance Comparison

The Complete utilizes a clean and dirty bag set up.
The Complete utilizes a clean and dirty bag set up.
Photo: Jessica Haist


The Sawyer 4L has a .1 micron filter size. This means that it can effectively filter out bacteria, protozoa, and Cryptosporidium. The Sawyer Complete 4 Liter Gravity Water Purification System is a slightly different product that is bulkier and more expensive - but its filter is .02 microns and filter's out viruses - so if you're thinking of traveling abroad that could be a good option and is similar to the Sawyer 4L Water Filtration System, we were confused about the difference between these two products for a while!

As with all of Sawyer's products, this filter has a very long life and comes with a 1 million gallon guarantee — which virtually means a lifetime warranty.

The Complete's dispensing cap will only thread on upside down - an...
The Complete's dispensing cap will only thread on upside down - an oversight by Sawyer we think.
Photo: Jessica Haist

The one reason why this Sawyer did not receive a higher mark in this category is because we have doubts about how market ready this product is; some of its components are of questionable integrity like the dispensing cap that only screws on upside-down and the strange hose quality. All this makes us lack confidence in the quality and reliability of this product.

Trying to pour water from the Sawyer Complete's malfunctioning...
Trying to pour water from the Sawyer Complete's malfunctioning dispensing cap.
Photo: Jessica Haist

Ease of Use

It took us a bit of time to figure out what connects to what and how to use this product, but it is relatively well labeled and color-coded once you know what all the parts do. Similar to the Platypus GravityWorks, it has a dirty (gray) water bag and a clean (blue) water bag. We were excited at the potential to use this as our hydration system as well, but were disappointed when we discovered that we had to provide our own mouthpiece/bite valve for the drinking tube provided — why wouldn't Sawyer just include the bite valve with the tube if the tube's only purpose is for a hydration system? You can hook the MSR AutoFlow up to your hydration bladder to fill easily so we still prefer to carry this unit and our own bladders that come with bite valves.

We like the idea of being able to use the Complete as a hydration...
We like the idea of being able to use the Complete as a hydration system, but don't want to carry the heavy dispensing cap with us in the back country (replaced here with an MSR cap that fits) and we had to use our own mouth piece as one is not provided.
Photo: Jessica Haist

Treatment Capacity

As we mentioned, this filter has a one million gallon guarantee so it will last forever — or you can get a new one! We like gravity filters because they are so easy to use in large group settings and discovered we could unclip various parts of the Water Filtration System's hoses to fill bottles or bladders that were not compatible with the hose attachment system. Sawyer says "Once the blue reservoir is full, hang by its handle to fill water bottles, containers, and pots and pans from the dispensing cap." We did not find the dispensing cap very helpful because it only screwed on upside-down, spilling water all over the place when we used it. We were not super excited to bring it with us in the backcountry because it weighed 2.3 ounces on its own!

You can un-clip the filter from the clean bag end and use it to fill...
You can un-clip the filter from the clean bag end and use it to fill any other container, which makes is a decent filtration method for groups.
Photo: Jessica Haist


The Sawyer 4L Filtration is one of the speedier filters out there, filtering one liter per minute in our timed test. The Katadyn Gravity Camp 6L was faster at 40 seconds per liter!


We were disappointed in how much this system weighs. It does have the benefit of extra storage with the two reservoir bags, like the GravityWorks and we used the clean water bag as our hydration pack when backpacking to reduce the number of water carrying devices we brought along, which was nice. However, the Sawyer weighs in at a hefty 17 ounces, five ounces more than the Platypus GravityWorks. We think some of that weight can be shaved with getting rid of the bulky, heavy dispenser cap — we switched it out for an MSR bladder cap that was the same size — lightening up some of the other components. We like the more durable bag materials of the Sawyer over the Platypus model.

The dirty bag has a handle for convenient filling, which is nice but...
The dirty bag has a handle for convenient filling, which is nice but we're not certain it's necessary and adds weight to the overall system.
Photo: McKenzie Long

Best Applications

If Sawyer can make these few tweaks and include a bite valve with their drinking hose, we think this could be a versatile filtration system for backcountry trips with large groups or even for a solo hiker. Right now it's a bit too heavy for one person to carry on adventures, so it's best for groups.

The Complete also comes with a strap to attach the dirty water bag...
The Complete also comes with a strap to attach the dirty water bag to any tree branch.
Photo: Jessica Haist


At $150, the Sawyer 4L Water Filtration System is the most expensive of the gravity filters we've tested and we don't think it is the best value. The filter does have an extremely long life, so that makes up for the price to some extent, but we still think the Platypus GravityWorks, our Editors' Choice winner, is a better value for a better product at this time.


This s a fast and reliable filter that lasts a really long time, but the product itself needs some improvement in its components and weight. We hope Sawyer reads this and takes our recommendations to heart. We think the Sawyer 4L Water Filtration System is currently incomplete, but has a lot of potential to be great!

Jessica Haist