Merv 13 Pleated Air Filter - 23 3/8" x 23 3/8" x 1" Quantity:12-pack the greater it's resistance to

the greater it's resistance to airflow

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

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

PLEASE NOTE: Dimensions listed are HxWxD

Merv 13 Pleated Air Filter - 23 3/8" x 23 3/8" x 1" Quantity:12-pack the greater it's resistance toAny Kind of Filter's Extended Surface Pleated Filters outperform ordinary furnace filters with medium efficiency and are designed for lower pressure drop, and long service life which reduces HVAC equipment maintenance and energy costs. A higher MERV rating means that the air filter that you are about to purchase possesses a higher amount impurity filtration ability than your ordinary filter.