GravityWorks 6L

The Platypus GravityWorks 6L is a straightforward, reliable gravity filter system designed for groups. Its main appeal lies in its simplicity and capacity: hang it, fill the dirty bag, and let gravity do the work. The 6-liter dirty reservoir pairs with a 6-liter clean reservoir, providing ample processed water for several people at a basecamp or on a multi-day trip without constant refilling. The hollow fiber filter itself is fairly robust and consistently delivers clean water without the fuss of pumping or the wait of chemical treatment.

From a construction standpoint, the bags are made from a durable, laminated film, typical of Platypus products, which holds up well to repeated use and backcountry abuse. The filter cartridges are replaceable, extending the life of the overall system. While not the lightest option if every gram counts for a solo fast-and-light trip, for its intended use—group water purification—its weight is perfectly acceptable, especially considering the volume of water it can process. Packability is good; the system rolls up reasonably small, fitting easily into a pack's main compartment or side pocket without being overly bulky.

Performance-wise, the flow rate is consistently good, clearing 6 liters in just a few minutes, which is a major time-saver compared to hand pumps or squeeze filters for larger groups. Backflushing is also simple and effective, helping to maintain flow rates over time. When compared to other gravity filters in its class, the GravityWorks stands out for its balance of capacity, flow, and user-friendliness. It's not the cheapest filter on the market, but its durability and efficiency make it a worthwhile investment for anyone regularly needing to process significant volumes of water for a group.