Access potable water anywhere. Our unique and versatile 28MM inline filter threads directly onto popular 28MM opening bottles and flasks and is equally easy to install in any of our reservoirs and caps with a Plug-N-Play™ connect system. This versatile connectivity makes our filter a great backcountry water treatment solution whether you are squeezing your water from a Stow into another bottle, gravity filtering your water out of a Seeker or Pioneer water storage bag or filtering as you drink on the go from a Stow or HydraPak reservoir.