MSR Thru-Link Inline Filter

By Jason B

Final Update: MSR Thru-Link Inline Filter April 2020

I have used the MSR Thru Link Inline water filter on three more trips over the past month.  The first was an all day hiking loop in Shenandoah National Park combining the AT, Neighbor Mtn and Jeremy Run trails.  Temperatures were in the low 30s and in the teens when the wind chill was taken into account.  My second trip was an 18 mile trail run on the Maryland AT. Temperatures were in the 40s and breezy.  My third trip was an overnight backpacking trip on the Maryland AT.  Temperatures were in the low 50s and clear weather.

For my day hike and trail run, I used the MSR Thru Link filter connected to my Camelback hydration bladder. I used the Thru Link in a gravity filter configuration on the backpacking trip.

I evaluated the Thru Link on two main criteria – durability and ease of use.  Durability has been good.  No issues there. I don’t do anything special with the filter.  When I am backpacking, I keep it in a mesh bag with my gravity filter system.  When I was hiking and running it was attached to the hydration bladder and suspended from the water bladder pocket in my pack or running vest.  There are no obvious signs of wear on the outer casing.

The filter continued to be easy to use.  While hiking and trail running I connected the filter directly to the port on my hydration bladder as shown below.

Thru Link
MSR Thru Link set up with my Camelback Reservoir.

I found the filter to be easy to use this way – just put “dirty” water in the hydration bladder and drink.  There was a little additional resistance while drinking from the hose that was definitely noticeable, but was not as difficult to drink from as some of the other filters I have used.  I did not have any issues with this configuration while hiking. However, trail running was a different story.

I was cruising down the AT in Maryland, trying to determine why Pennsylvania thinks their section of the AT is more rocky than the Maryland section which is rock hell when I noticed that my back was wet and more than just sweat.  I reached back and felt the back of my running vest and it was soaked.  So I stopped and took off my pack to figure out what was going on.  It turns out that the Thru Link filter had come unseated from the hydration bladder connection point.  I pressed it back in, but it would not stay.  I eventually had to just disconnect it.

I am not sure why the filter would not stay seated in the connection on the water bladder. Maybe it was the jostling from running which is greater than while hiking.  Anyway, this is my only nit pick. Kinda sucks to be on a long run and lose the ability to drink water.

The filter continues to work well in the gravity set up.  While camping on the AT, I started my water filtering, then went on to set up my tent and begin prepping for dinner and by the time I am ready, I have clean water for dinner and drinks.

Gravity Set up camping at an undisclosed location

Overall, I have been very pleased with the MSR Thru Link and consider having a filter like this essential.  It is a mandatory accessory for my backpacking/camping kit as well as my survival kit.

Thanks to and MSR for allowing me to participate in this review.

Update 1: MSR Thru-Link Inline Filter February 2020

I have used the MSR Thru-Link inline filter on two backpacking trips on the Appalachian Trail in West Virginia and Virginia. Temperatures were in the upper 30s to the mid 50s on the first trip, and on the second trip, temperatures were in the upper 20s to the low 40s.  Neither trip had any precipitation.

I used the MSR Thru-Link filter in a gravity configuration on both of my trips. My test model was missing one of the hose to barb adapters, but I was able to connect it directly to the “dirty” reservoir of my gravity system.  (MSR sent me the missing piece and I will reference it more in my next update).

thru-link inline filter
MSR Thru-Link Filter attached directly to my Platypus gravity filter system

I mentioned that I look for two main characteristics with a water filter – durability and ease of use.  I will start with durability.

The durability has been great – I haven’t really done anything special  I have a mesh sack that I keep my gravity filter system in, and I just tossed the MSR Thru-Link in with everything else and put the whole system in the shove it pocket on my Gregory Paragon pack.  In camp it is either connected to the system or laying somewhere near my pack.  I stayed in AT shelters on both of my trips so I wasn’t worried about the filter sitting in dirt or anything, it was on the shelter floor.  If I was tent camping, I would try to make sure it was in my pack when not in use.

One issue with using any filter in the winter is keeping it from freezing.  I place the filter in a zip top bag and put it in my sleeping bag at night.  The temperatures were definitely below freezing for most of my second trip, so when it was not in use I kept it in a cargo pocket in my pants which were underneath a pair of insulated pants.

The ease of use has been superb so far.  My routine when I get to camp is to use my Platypus water bags to get water from the spring or creek.  I then pour the water from the bags into my “dirty” reservoir. Then I connect the filter and hose to the “clean” bag. I then usually go about setting up the rest of my camp.  Usually, even after getting camp set up I am still waiting for the 4 liters of unfiltered water to finish, but not with the MSR Thru-Link.  I had barely gotten my sleeping bag and pad laid out and the filter had already done 2 liters.  It wasn’t much longer before I had 4 liters of clean water.   The other hikers in the shelter were also impressed at how quickly the MSR Thru-Link worked, especially as they were futzing with a squeeze filter system from another manufacturer.

Overall, I am pleased with the MSR Thru-Link.  Over the next month or so I will use the filter inline with my hydration bladder. I am interested to see how well this configuration works.  I will continue to evaluate durability and ease of use.  Thanks for reading my first update.

Initial Thoughts

MSR is one of the leaders in the outdoor industry when it comes to water filtration.  They have a wide line up of filters; from the classic MiniWorks EX microfilter to chemical filtration with Aquatabs, and now they are adding a new microfilter the MSR Thru-Link inline filter.

MSR Thru Link Inline Filter
Image courtesy of the MSR website

The Thru-Link inline filter is just what it sounds like, a plastic housing that holds the filter material with a connection on either end.  Water is able to flow one direction through the filter material. MSR uses two stage filtration – fast flow hollow fiber and activated carbon.  The Thru-Link filter also comes with two Hose to Barb quick connect adapters which according to MSR should make the filter compatible with any hydration reservoir. MSR states that the filter will process 1.5 liters per minute and that it has a capacity of up to 1000 liters. The Thru-Link inline filter retails for $39.95.

I am excited to be able to use the Thru-Link inline filter over the next couple of months.  I am hitting the later stages of a trail running training block so I have to use it on my hydration reservoir on long runs in addition to using it on backpacking trips.

I will evaluate the MSR Thu-Link inline filter on the following characteristics – durability and ease of use.  I am hard on gear, so I am interested to see how the filter stands up to abuse.  I wonder if the plastic housing is sturdy or will I need to do something to protect it?  I should be able to suck water through the filter from a hydration reservoir – is this difficult?  Will the Thru-Link work with my current gravity filtration system?  These are just a few of my initial thoughts.  Please check back in about a month to see how the MSR Thu-Link inline filter has performed.

MSR Thru Link Filter
MSR Thru-Link filter in use at the David Lesser Shelter, on the Appalachian Trail in West Virginia

Thanks to and MSR for allowing me to participate in this review.