Merv 11 Pleated Air Filter - 6" x 21" x 1" Quantity:12-pack the greater it's resistance to

the greater it's resistance to airflow

Filtering inserts are shipped in an easily stored packet

Includes one Frame and PACK of 6 pads

Any Kind of Filter's Extended Surface Pleated Filters outperform ordinary furnace filters with medium efficiency and are designed for lower pressure drop

Merv 11 Pleated Air Filter - 6" x 21" 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.