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Alen · air purifier

Alen BreatheSmart FIT50 replacement filter

Use part FF50-Pure. Replace every 9-to-12-month lifespan.

The filter that fits

Maker lists this model

Alen FF50-Pure

BreatheSmart FIT50 HEPA Filter, Pure

Part number
FF50-Purealso sold as F40001
How many
1 per unit
How often
Replace every 9-to-12-month lifespan
Buy FF50-Pure on AmazonManufacturer page

Opens an Amazon search for Alen FF50-Pure. Check the listing says FF50-Pure.

See the sources

Other genuine options from Alen

Variants and kits the maker sells for this model. Same fit, different media or packaging.

Sources

High confidence: the manufacturer names this exact model on a live page. Each line is the page we read and the day we read it.

  • Which filter fits alen.com Maker's own page checked Oct 1, 2026
    BreatheSmart FIT50 HEPA Filter ... (FF50-Pure) ... Fits Model: BreatheSmart FIT50
  • How many web.archive.org Maker's archived page checked Oct 1, 2026
    Page for the BreatheSmart FIT50 (per its URL): Remove the used filter by pulling out on the pull strings ... insert it into the air cleaner with the pull strings facing outward. (The front side has the black mesh layer, known as the prefilter ...) (archive.org copy of 2025-10-09)
  • How often alen.com Maker's own page checked Oct 1, 2026
    9-to-12-month lifespan
  • Other genuine options alen.com Maker's own page checked Oct 1, 2026
    (FF50-Fresh) ... (FF50-Odor) ... (FF50-Pure) ... (FF50-VOC)
Show all 5 sources

Which filter fits

  1. alen.com Maker's own page checked Oct 1, 2026
    BreatheSmart FIT50 HEPA Filter ... (FF50-Pure) ... Fits Model: BreatheSmart FIT50
  2. alen.com Maker's own page checked Oct 1, 2026
    BreatheSmart FIT50 HEPA Filter variants: Pure F40001; Fresh F40002; VOC/Smoke F40003

How many

  1. web.archive.org Maker's archived page checked Oct 1, 2026
    Page for the BreatheSmart FIT50 (per its URL): Remove the used filter by pulling out on the pull strings ... insert it into the air cleaner with the pull strings facing outward. (The front side has the black mesh layer, known as the prefilter ...) (archive.org copy of 2025-10-09)

How often

  1. alen.com Maker's own page checked Oct 1, 2026
    9-to-12-month lifespan

Other genuine options

  1. alen.com Maker's own page checked Oct 1, 2026
    (FF50-Fresh) ... (FF50-Odor) ... (FF50-Pure) ... (FF50-VOC)