Why it matters
The Blueair Classic 400 Replacement Filter is a replacement filter.
Made for Blueair's Classic 400 purifiers. The model label is usually on the back or under the filter door; match it before ordering.
Construction: Particle.
Most purifier HEPA filters last six to twelve months in normal use; follow the unit's filter indicator and replace sooner in smoky or pet-heavy homes.
This is the particle stage: the pleated HEPA or HEPA-type media catches dust, pollen, dander and smoke particles, and it gets better at catching them as it loads, until the airflow drops. When the intake side turns gray or the fan sounds strained on its usual setting, it's due.
Use the filter made for your exact unit: purifier filters seal against their own housing, and a close-but-different filter lets air bypass the media.
Compared with the Blueair Classic 200 Replacement Filter: rated room size 279 square feet here vs 240 square feet.
Who it's for, and who should skip it
Good fit if
- Blueair Classic 400 owners
- Keeping rated performance
Look elsewhere if
- Other purifier models
Pros and cons
Pros
- Exact-fit replacement
Cons
- Only fits its own unit family
- A recurring cost of owning the purifier
Limitations to weigh
- Specifications are the maker's or seller's own figures; check fit against your equipment's model number and the actual size.
Specifications
The bracket shows where each figure comes from.
| Model number | Classic 405 | Retailer |
|---|---|---|
| Room coverage | 279 square feet | Retailer |
| Filter type | Particle | Retailer |
Alternatives worth comparing
More air purifier replacement filters we cover
- Medify Air MA-112 Filter Set $138.99
- DerBlue Replacement Filter for Shark HP100
- Omaeon HyperHEPA Filter for IQAir HealthPro Series
- Blueair Blue Pure 311 Particle + Carbon Filter $34.99
- Coway Airmega 150 & 160 Filter Set $49.99
All air purifier replacement filters, compared in one table · Every Blueair product we cover
Final verdict
A solid choice for blueair Classic 400 owners. Confirm the model it fits before ordering.
Where to buy
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