Merv 13 Pleated Air Filter - 27 1/2" x 33 1/2" x 1" Quantity:12-pack A higher MERV rating means

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

This is designed to fit into 1" Return Air Grilles

Because we specialize in custom air filters

some just refer to them as electrostatic filters

if not you can measure it or check the HVAC unit and the owner‰۪s manual

Merv 13 Pleated Air Filter - 27 1/2" x 33 1/2" x 1" Quantity:12-pack A higher MERV rating meansAny 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.