Practical Pleated Air Filter (2-Pack) - 17 1/2" x 23 1/2" x 5" Quantity:Default the A+2000 uses stage loading

the A+2000 uses stage loading

PACK of 6 pads for Pad and Frame Air Filters

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

You may know them as washable air or even permanent air filters

with each stage capturing progressively smaller particles inside the filter

Practical Pleated Air Filter (2-Pack) - 17 1/2" x 23 1/2" x 5" Quantity:Default the A+2000 uses stage loadingYes, 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