Merv 11 Pleated Air Filter - 11 3/4" x 11 3/4" x 1" Quantity:12-pack if not you can measure

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

The A+2000 line is easy to maintain with no need to buy oils or adhesives to enhance effectiveness

Includes one Frame and PACK of 6 pads

and the greater the pressure drop it creates

The "Practical Pleat" contains over 500% greater surface area than a MERV 10 one-inch pleat

Merv 11 Pleated Air Filter - 11 3/4" x 11 3/4" x 1" Quantity:12-pack if not you can measureAny 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.