20x20x5 (19.75x19.88x4.38) MERV 11 Aftermarket Lennox Replacement Filter (2 Pack) Lennox part numbers X0585, X8305, X8308, X7930 and X7935. Fits Lennox and Healthy Climate model numbers HCC14-23, HCF14-10, HCXF14-10 and HCF14-16. Nominal size is 20 x 20 x 5. Actual size is 19 3/4 x 19 7/8 x 4 3/8. It has 98% efficient filtration media. This is an aftermarket filter.