28mm InLine Water Filter


HydraPak's unique and versatile 28mm InLine Filter threads directly onto many popular 28mm opening bottles and works in-line with their reservoirs as well. It can be used with their 1L Stow bottle, our Seeker Hydration Bundle, and our hydration-bundled Sandur, Choss, and Hopper bags. This versatile connectivity makes their filter a great backcountry water treatment solution whether you are squeezing your water from a Stow into another bottle, gravity filtering out of a Seeker, or filtering as you drink from a HydraPak reservoir.

Filter, Cap Adapter and Backflush Adapter

28MM Thread Compatible
Easily thread the filter onto some of the most popular backpacking bottles and flasks including the HydraPak Stow 500ML and 1L and the 1L Smart Water Bottle.

Plug-N-Play Compatible
Easily connect and disconnect the filter from the Plug-N-Play ports in reservoirs and caps.

Fast & Safe Filtration
Removes 99.99% of E Coli & Parasitic cysts. Filters approximately 1,500 liters of fresh water at a rate of >1 L per minute.

  • Effectively removes common waterborne bacteria, such as E. coli (99.9999%), and parasitic cysts (99.999%) per EPA Guide Standards and NSF P231 and microplastics (99.999%) per NSF 42 greater than or equal to 3.0 microns in size
  • Single stage < .2 micron hollow fiber filter
  • Effective against: protozoa, cysts, and bacteria
  • Meets or exceeds EPA protocol
  • Filters at >1L/minute
  • Filter life approx. 1500L



47 g / 1.6 oz (filter only)


PP/POM, EPDM, Silicone, Hollow Fiber

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