Merv 11 Pleated Air Filter - 12" x 12" x 1" Quantity:4-pack some just refer to them

some just refer to them as electrostatic filters

This is a 5" MERV 10 HIGH PERFORMANCE AIR FILTER

This design enables A+2000 custom air filters to maintain performance over the years

Unlike some permanent custom air filters

than standard fiberglass filters purchased at retail outlets

Merv 11 Pleated Air Filter - 12" x 12" x 1" Quantity:4-pack some just refer to themAny 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.