Platypus GravityWorks Water Filter
$120, 12 oz. (including mesh stuff sack)
moosejaw.com
There are two things I don’t like about filtering water in the backcountry: the weight of a filter in my pack and the time that pumping water requires. The GravityWorks filter addresses both gripes, but especially the latter. Here’s a filter that requires no pumping. It’s easy: Fill the four-liter reservoir labeled “dirty” with water from a creek or other source and seal its opening. Hang it from a tree branch or set it on elevated ground. Attach the quick-release hose-and-filter unit to the dirty reservoir, and then the “clean” reservoir to the hose below the filter. When you set the clean reservoir down in a spot lower than the dirty one, gravity does the work of filtering for you.