Practical Pleated Air Filter (2-Pack) - 21 1/2" x 23 1/2" x 5" Quantity:Default The permanent frame is constructed

The permanent frame is constructed of space-age plastics that are resistant to corrosion

the "A+2000" brand Permanent Washable Electrostatic custom air filters are truly quality products

such as dust

Because we specialize in custom air filters

Practical Pleated Air Filter (2-Pack) - 21 1/2" x 23 1/2" x 5" Quantity:Default The permanent frame is constructedYes, 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