WEIGHT: 11.5 oz
PROS: Very convenient, good for groups
CONS: Heavy, expensive, doesn’t filter viruses
The convenience of the Platypus GravityWorks is tough to beat, especially for large groups. To use the GravityWorks, simply fill up the “dirty” water bag, hang it above the “clean” bag, and let gravity do its thing. The main benefit? No tedious pumping or squeezing required. This is especially beneficial for large groups, when filtering a lot of water can quickly become obnoxious. There is a downside to the convenience of the GravityWorks, and it comes in the form of weight. We prefer to travel as light as possible on our backcountry trips, so we only take the GravityWorks when we can share its weight with a group. Platypus also makes the GravityWorks in a 2 liter system and 2 liter bottle kit, but we prefer the 4 liter model.
Like most filters, the flow rate of the GravityWorks will diminish over time depending on how dirty the water you filter is. Periodic backflushing will help with flow rates, but eventually the filtration unit will need to be replaced. Like most filters designed for the US market, the GravityWorks won’t filter out viruses (read “Viruses” section above), but that shouldn’t be a dealbreaker unless you plan to use it internationally.