18" X 18" X 1" Lifetime Permanent Washable Filter

Permatron 3856-1818LRG | Our#: 178208

1 Year Purchase Guarantee - Free returns for a year, up to $1000 of purchase protection.


18" X 18" X 1" Low-Resistance, Electrostatic Permanent Washable Filter

(actual size - 17-1/2" X 17-1/2" X 7/8")

Never buy another filter!  Our permanent washable filter is designed to provide great value and last a lifetime.   This durable filter is constructed with a combination of woven polypropylene media supported by heavy-duty steel mesh in a galvanized steel frame. The filter carries a lifetime warranty and is ideal for heat pumps, sensitive 90+ efficient furnaces and systems with limited air flow.  This is the best and last filter you will ever buy.


  • Designed to minimize initial resistance to airflow
  • Reduces the number of pollutants and allergens in recirculated air and keeps your HVAC system clean
  • Uses natural static electricity to attract and capture airborne particles
  • Washable - cleans up in minutes
  • Includes anti-microbial polymeric protection
  • Durable steel frame
  • Dirt won't get caught in the filter during washing - due to specially-designed drainage ports in the filter frame
  • Lifetime warranty

Clean Monthly by rinsing your filter with running water.  For tough dirt and/or grease, use a mild detergent (i.e., 409 or Simple Green) and rinse thoroughly with warm water.

Average arrestance efficiency - 74%
Initial resistance - 0.07" w.g.
Dust holding capacity - 110 grams

18" X 18" X 1" Lifetime Permanent Washable Filter
18" X 18" X 1" Lifetime Permanent Washable Filter Reviewed by 3
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Displaying reviews 1-3:

By Robert M.


 5 of 5

Good product wrong size


Although my filter stated 18" x18" x1" in actuality it measured 18"x14"x1", leaving an overhang by 4". Too large for the filyer to fit tight..

BOTTOM LINE: Yes, I recommend this product

By al


 4 of 5

18x18 permanent filter


The filter looks good. Arrived very slightly damaged - not enough to affect function, and appearance doesnt matter - filter goes inside furnace, out of sight. Damage is shippers responsibility, not Discount Filters. discount Filters.

BOTTOM LINE: Yes, I recommend this product

By Duraid


 3 of 5

Performance is all my concern


I wish the metal frame was built in a stronger construction since it's a permanent usage

BOTTOM LINE: Yes, I recommend this product

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