Zephyr 18x18x3 MERV 11 Media Air Filter for Return Air Grilles. Qty 3
This is a top-hat style filter has a self-sealing flexible 3/4 foam gasket that eliminates dirty air bypass, a superior design to filters that use a rigid gasket. The foam gasket holds the filter in place preventing the filter from settling (noise) when your HVAC system cycles on and off.