Platypus Gravity Works Water Filtration system. Platypus Gravity Works Water Filtration System, USE TEST REVIEW Editor: Cory McLaughlin Follow us on Instagram @ireviewgear Just the Facts: Update: Below PRODUCT DETAILS 2L An ultralight and versatile water filter that makes it easy to treat water for 2-4 people on backpacking, hiking, and backcountry trips, the pump-free […]