MSR Guardian Gravity Purifier

MSR is a company synonymous with quality backcountry gear, and their latest offering, the Guardian Gravity purifier (GGP), is no different. I actually shared my friend’s older MSR water purifier during my bikepacking ride through the Spanish Sierra Nevada, and I was really impressed. On the bike, hiking or overlanding, it’s remarkable how quickly you get through your water provisions, and the ability to filter water in remote areas is a priceless commodity. The new Guardian takes water filtration to the next level, removing viruses, bacteria, protozoa, sediment and microplastics hands-free.

The GGP boasts an impressive 10-litre reservoir, thus supporting the daily water requirements of multiple people (or a fantastic emergency option for refilling a vehicle water tank). The “gravity” element means there’s no pumping required, so simply hang where convenient, and let the filter do all the work. The effortless functionality and the impressive flow rate (a litre in two minutes, which is two and a half times faster than the next closest competitor—optimal reservoir hang height six feet) means in just 20 minutes I can have 10 litres of fresh drinking water.

Furthermore, in an emergency, I could fill my Syncro’s 17-gallon (80-litre) water tank in under three hours, which is really impressive for such a small portable filter. The reservoir can be easily filled at sinks or streams, and packs down extremely small in its dedicated carry case (perfect for hiking, bikepacking, overlanding or general travel). Backcountry waste is a real issue, water sources are becoming increasingly polluted, and more plastic waste can be found in popular beauty spots. The GGP both protects you from contaminated water, and thanks to its 3,000+ litre lifespan (equivalent to purchasing 3,000+ plastic water bottles), it also reduces our environmental footprint. The GGP was first intended for military use, and has a NSF P248 Testing Standard. It also meets U.S. EPA Guide Standard and Protocol for testing microbiological purifiers, which is the most rigorous scientific certification for proving a treatment device safely removes claimed contaminants from challenging wilderness water sources (making Guardian devices the market’s only purifiers to pass the military standard P248 testing). The two-stage purifier also includes activated carbon to reduce chemicals and unpleasant tastes/odors, and is simple to clean with no backflushing required (simply opening the purge hose flushes the system to clean it and maintain flow rate). Finally, it includes a universal bottle adapter, so that the GGP connects seamlessly to your favourite water bottle or bladder.


The MSR GGP is a great product that manages to be lightweight and compact, whilst offering a generous capacity, and a class-leading flow rate. Military grade protection, excellent portability, and effortless usage makes this purifier a must have for backcountry adventurers.

$249 |

No money in the bank, but gas in the tank. Our resident Bikepacking Editor Jack Mac is an exploration photographer and writer living full-time in his 1986 Vanagon Syncro but spends most days at the garage pondering why he didn’t buy a Land Cruiser Troopy. If he’s not watching the Lord of the Rings Trilogy, he can be found mountaineering for Berghaus, sea kayaking for Prijon, or bikepacking for Surly Bikes. Jack most recently spent two years on various assignments in the Arctic Circle but is now back in the UK preparing for his upcoming expeditions—looking at Land Cruisers. Find him on his website, Instagram, or on Facebook under Bicycle Touring Apocalypse.