Water filter (hollow fiber)

Water

Compact squeeze/straw filter that removes bacteria and protozoa from wild water.

Approx. cost
$20–$45
Weight
2–4 oz
Used in
1 kit

Purpose

Make streams, lakes, and questionable taps safe to drink on trips and in emergencies.

More specific types

Water Filter” is a broad category in the shared vocabulary — kits can also reference these narrower types:

  • Hollow-fiber filter you squeeze water through — the lightweight default.

  • Chemical treatment — slow but nearly weightless backup.

See “Water Filter” in the full item tree →

Used in kits

Alternatives

  • Purification tabletsWeigh nothing; 30-min wait and a taste.
  • BoilingAlways works; costs fuel and time.

Maintenance notes

  • Backflush after trips to maintain flow rate.
  • CRITICAL: a hollow-fiber filter that has frozen while wet is silently ruined — replace it.

Buying considerations

  • Check compatibility with standard soda-bottle threads.
  • Note the filter’s rated lifetime in liters.

⚠️ Safety notes

  • Hollow-fiber filters do not remove viruses or chemicals — fine for North American backcountry, insufficient for sewage-contaminated water.

Page history & editing

Revision status: approved Last edited 2026-07-01 by human editor