Lennox Healthy Climate 20x25x5 x6673 MERV 11 Box Filter Replacement for HCXF20-10, HCF20-10 20X25X5 MERV 11 Replacement for Lennox X6673 Replacement for EXPXXFIL0020, EXPXXUNV0020, EXPXXLMC0020, FILCCCAR0020 X6673 Replacement Filter for Lennox and Honeywell Replace ment for FC35A1027, FC100A1037, FC200E1037, F35Expandapac