Nov 01, 2021 · Best Backpacking Water Filter of 2021. We tested backpacking water filters and treatment systems from Platypus, Sawyer, Katadyn, and others to find the best option for your adventures. Photo: Amber King. By Amber King, Jessica Haist, and Trish Matheny. Monday November 1, 2021. Our Editors independently research, test, and rate the best products.