20 x 24 x 4 MERV 8 Furnace / Air Conditioner Filters. Case of 6 filters. MERV 8Premium Quality8 Pleats per Lineal Foot35.2 EfficiencyNotesDQP40 Pleated Filters are available in 1 2 and 4 depth. Theelectrostatically charged 100 synthetic graduated density media iscontinuously bonded to a 30 gauge galvanized corrosion resistantexpanded metal support grid with an effective open area of 96. Themedia is resistant to a wide range of chemicals does not absorb moistureand will not support microbial growth.The controlled pleat spacing maximizes surface area and dust holdingcapacity and is bonded to the enclosure frame to prevent dust bypass.The enclosure frame is constructed of high wet strength moisture resistantbeverage board. The diagonal support members of the frame are bondedto the entering and exiting apexes of each pleat to prevent pleat collapseand filter bowing.