Merv 13 Pleated Air Filter - 11 1/2" x 21 1/2" x 1" Quantity:12-pack UL/ULC listed

UL/ULC listed

And there are no metal parts that could lead to corrosion or oxidation within the filter

from the air stream

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 - 11 1/2" x 21 1/2" x 1" Quantity:12-pack UL/ULC listedAny 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.