Practical Pleated Air Filter (2-Pack) - 6" x 20" x 5" Quantity:Default some just refer to them

some just refer to them as electrostatic filters

28X Increased Efficiency

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

They are easy to install with custom air filters made to the sizes that you specify

Practical Pleated Air Filter (2-Pack) - 6" x 20" x 5" Quantity:Default some just refer to themYes, 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