MSR AutoFlow
The beauty of gravity filters is that, well, gravity does all the work. We’ve tried them all, and this one is the best.
Brand: MSR Gear Reviews
Model: AutoFlow
Simplicity
By day two of a trip to Tahoe, every member of our 12-person group had ditched pumps and squeeze bags to fill up from this 4-liter reservoir. Hang the bag from a tree, set your bottle below, and let gravity do its thing. The filter eliminates bacteria and protozoa at 1.75 liters per minute.
Maintenance
Backflushing is as simple as lifting the clean-water bottle above the fill bag. A first-in-class indicator alerts you if the hollow fibers break, rendering the filter useless (read the directions).
Durability
The filter cylinder is fitted with rubber bumpers to protect the housing from drops, which can break hollow fibers. We manhandled the filter bag around camp, plopped it on rocks, and banged it up hanging it from branches, but never sprung a leak or suffered other damage.
$120; 10.5 oz.