This quality non-OEM filter media fits the Spacegard 2400 filter housing. It replaces the Aprilaire 401 (Space-gard 401) OEM filter media.
As a notable improvement over the OEM, the replacement features non-tear poly filter media. MERV rating of 11 (MERV Rating of OEM part is 10). The higher the MERV rating, the higher the arrestance of particulate matter (or said differently, higher MERV means more filtration).
Nominal size: 28″ x 6″ (actual size: 27 1/8″ x 6″)