Improve the indoor air quality of your home with replacement 18X24X4 Merv 11 furnace filters from Merv Filters LLC. These air filters are highly efficient and capable of removing 90% of airborne particles. We specialize in providing electrostatically charged, 100% synthetic media made 18X24X4 Merv 11 air filters to remove 65% to 79% of 1.0 to 3.0 microns and 85% percent of 3.0 to 10.0 microns.
Our 18x24x4 Merv 11 furnace filters are highly recommended for residential and commercial areas where higher stands of clean and healthy air are required. Our 18x24x4 Merv 11 filters are made of high-quality material and will last for a long time. However, we recommend you to change the furnace air filter every 3 months. But if you are using 18x24x4 Merv 11 air filters in hospital or school, we suggest you replace the filters every 2 months for better filtration and healthier & cleaner air.
Important Note: Before placing your order for an air filter, make sure you measure the weight, height, and thickness very carefully. Because the actual size of the air filter is different from the nominal size of the filter. The nominal size is slightly bigger and round in shape. So if the nominal size of your air filter is 18x24x4, its actual size is 17.5×23.5×3.75.