12x30x1 MERV 2 Non Pleated Air Filter Replacement Filters (Actual Size 11.75 x 29.75) - 3 Pack Height_18in + Product Details Size -

+ Product Details Size - 4"w X 32"h is the size for the duct opening measurement only

please note that the total outer dimensions of the grille measure 7" in diameter

rust-free aluminum

+ Product Details Size – 26" x 36" or 36" x 26" is the size for the duct opening measurement only

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12x30x1 MERV 2 Non Pleated Air Filter Replacement Filters (Actual Size 11.75 x 29.75) - 3 Pack Height_18in + Product Details Size -+ Product Details 12" x 30" x 1" replacement air filters for your furnace, air conditioner, heat pump, or HVAC system (actual size: 11. 75" x 29. 75") A unique combination of cotton & synthetic fibers gives you the most filtration and the least air resistance equals great air & easy airflow for your system. The non pleated design provides low airflow resistance while still effectively capturing dirt and particles such as standing dust, spray paint