As the saying goes, you can last three minutes without air, three days without water and three weeks without food. Unless of course you're a breatharian in which case GET A LIFE! Seriously though, those are very rough guides depending on a lot of other factors, but let's just stipulate that we need a lot of water, and often. Sometimes the trick is not finding water, but making it safe enough to drink.
Icon is a company that specializes in the making-safe part, with a wide range of products from the personal to the professional, and their Lifesaver technology has been proven in the field through real-world use by military and humanitarian missions. We're taking a look at the Liberty, a portable filter bottle with a built-in hand pump.
The Liberty is actually a purifier by the normal definition, in that the ultrafiltration cartridge takes out viruses and cysts in addition to bacteria. The Liberty is a great piece of engineering; the filter actually stops working when it needs to be changed, which should be around the 2,000 litre mark. There's a loop for a carabiner, a five-foot hose for accessibility to sources and to keep your hands away from contamination, an adjustable flow valve and transparent windows on the sides to check water level.
The Liberty holds 400ml/13oz of water, perfect for hydrating at rest stops. It weighs .68kg/2.2lbs dry, which is substantial but much less than carrying any reasonable amount of water. If you're the type who likes to be prepared, it's hard to do better than a Lifesaver Liberty.