MSR's Pocket-Sized TrailShot Water Filter - Review


Clean water is one of those amenities many of us take for granted – we turn on the faucet, fill up our water bottles, and head out for a ride without a second thought, confident that the water coming out of the tap is free from any malicious creepy-crawlies. It's a different story when you're outside, away from pre-treated water; even the most innocuous looking streams can harbor all sorts of nasty bacteria just waiting to wreak havoc on your insides.The MSR TrailShot filter is designed to make drinking water out on the trail less of a game of Russian roulette, all without taking up much room in your pack or jersey. According to MSR, it meets U.S. EPA drinking water standards and NSF protocol P231 for removal of bacteria (99.9999%), protozoa (99.9%), and particulates.

MSR TrailShot Details• Hollow fiber filter; pore size: .2 micron• Flow rate: 1 liter per minute• Effective against bacteria, protozoa, and particulates• Cartridge life: 2,000 liters• Weight: 159 grams• Made in USA• MSRP: $49.95 USD


Slightly bigger than the bulb used to inflate a blood pressure cuff, the TrailShot weighs a scant 159 grams, costs $49.99 USD, and can filter one liter of water per minute. There are some very reasonable limits to what it will remove – it won't make seawater drinkable, or protect you from radiation, something to keep in mind if you get thirsty while riding through a Superfund site.
MSR TrailShot review
The screen on the prefilter keeps larger particles from getting into the plastic tube.
MSR TrailShot review
The TrailShot uses hollow fibers that have microscopic pores to filter the water as it's forced through the replaceable cartridge.


If you can make a fist, you can operate the TrailShot. All that's necessary is placing the prefilter – the red-tipped end of the hose – into the water source, squeezing the bulb 10 times to prime the system and then continuing to squeeze the bulb to fill up your water bottle, hydration bladder, or mouth. It's that simple. MSR recommends cleaning the filter cartridge every 8 liters, a process that only takes a minute or two. The cartridge should last for 2,000 liters of water, and when it does come time to replace it, a new one goes for $34.99 USD.
The TrailShot takes up about as much room as a large avocado, and can easily be cleaned or serviced in a matter of minutes if necessary.


These days, I try to avoid wearing a backpack at all costs in order to keep my neck and shoulders happy. Even on longer rides I can usually get by with a hip pack and a water bottle or two, but that program gets a little trickier during hot summer weather, when it's difficult to carry enough fluid to keep up with the amount of sweat I'm producing. There's also the fact that there are still a number of bikes out there that won't accomodate a water bottle, or if they can, it's mounted on the downtube, directly in the line of fire from whatever squishy grossness you run over. That's where the TrailShot comes in – its small size makes it easy to stick into a hip pack or jersey / bib shorts pocket, and then use it to refill a water bottle over the course of a ride, or use like a personal water fountain and drink directly from it. Of course, you'll need to know that there's a water source at some point on your ride, but I'm fortunate to live in an area where streams, lakes, and rivers are plentiful.The TrailShot is dead simple to operate, and its filtering speed matches MSR's claims – a minute or two of squeezing and you've got a bottle full of drinkable water. The amount of water that's produced per squeeze is impressive, and the amount of effort required is minimal. So does the filter actually work? Well, I've been using it regularly for the last few months to drink out of a variety of water sources, and I'm happy to report that I don't seem to have picked up any new organisms in my intestines – that's a win in my book.

Pinkbike's Take

bigquotes Simple, effective, and very reasonably priced, the TrailShot is highly recommended for anyone who spends time outdoors. After all, wouldn't you rather be out riding instead of sitting in a doctor's office because you decided to forgo filtering and drank from a contaminated stream? Mike Kazimer