Customize the MAX with any Series IV filter cartridge for use in emergencies, international travel, backcountry excursions or anywhere the water may be of questionable biological or chemical quality. The quick connects make it simple to plug into any hydration pack or inline system without a need to replace your current connectors. Plug in the patented bite valve to convert your MAX into a straw filter or gravity system.Features : Backcountry Plus Filter Lightweight a compact 1 oz. (71 g) packable protection Customizable to accept any Series IV cartridge Connects to reservoirs, gravity, and DIY systems via quick connects Fits all Aquamira pressurized reservoirs, for pressure-assisted filtration on the trail Includes Miraguard Antimicrobial Technology suppresses the growth of bacteria, algae, fungus, mold and mildew within the filter media Certified lead free (NSF/ANSI-372) BPA free, chemical free, and iodine free Filter made in the USA