Water filter (hollow fiber)

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:

• Squeeze FilterSubtype

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

• Purification TabletsSubtype

  Chemical treatment — slow but nearly weightless backup.

• Gravity Water FilterSubtype

  A hang-and-wait filter that treats liters of water with no pumping.

Used in kits

• Compact Camping Kit

  Camping

• Overland Camp Kitchen Kit

  Camping

• Backcountry Water Treatment Kit

  Camping

• Alaskan Float Trip Fishing Kit

  Fishing

• Ultralight Overnight Backpacking Kit

  Hiking & Backpacking

• Search and Rescue Field Team Kit

  Work & Field Operations

Alternatives

• Purification tablets— Weigh nothing; 30-min wait and a taste.
• Boiling— Always 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.