RapidPure Pioneer Straw
Lightest purifier
The Pioneer Straw filters out bacteria, viruses, and heavy metals, reduces bad tastes—and it’s barely thicker than your thumb. Thank RapidPure’s unique UltraCeram, a filtration technology that attracts and traps viruses and bacteria using positive electric charges rather than hollow fibers. The system is rated for 750 liters—a bit lower than average—but you get a better flow rate than hollow-fiber filters with the same level of virus protection. Big bonus: It also means that the Pioneer will work even if it freezes, since there aren’t pores to expand. (Effectiveness drops if it freezes multiple times, though.) It’s durable, too: “I accidentally dropped it on river rocks a couple of times and continued to use it with no ill effects,” one tester reports. Our testers sucked up stream water at a liter per minute during a weekend in Colorado’s Sawatch Range. The only downside to this tiny purifier is that you’ll have to either sip directly from the water source or from an open water bottle: It doesn’t screw onto bottles or connect to hoses.
$30; 1.9 oz.