Lennox X6673 20x25x5 MERV 11 HCF20-16 Sale $32.99 Original Filter Replacement X6673 Original Filter Sale by Atomic Features great pricing on 1 pack and 2 packs of the X6673 20x25x5 MERV 11 Furnace Filter Replacement for HCF20-16 starting at $32.99. Atomi