Practical Pleated Air Filter (2-Pack) - 18" x 21" x 5" Quantity:Default than standard fiberglass filters purchased

than standard fiberglass filters purchased at retail outlets

degrade and restrict air flow

Can be ordered in packages of 2 each only

Filtering inserts are shipped in an easily stored packet

Instead of face loading (particles captured on the outer surface of the filter)

Practical Pleated Air Filter (2-Pack) - 18" x 21" x 5" Quantity:Default than standard fiberglass filters purchasedYes, we even have the odd sizes! The "Practical Pleat" media is up to 28 times more effective at capturing particles than standard fiberglass panel filters. In general, the more efficient a filter is at removing particles, the greater it's resistance to airflow, and the greater the pressure drop it creates. One way to overcome this problem is to increase the surface area of the filter media. The "Practical Pleat" contains over 500% greater surface