The alternative filter would be the Lennox X8789 click here to learn more about the Lennox X8789

Lennox Healthy Climate MERV 16 replacement furnace filter - X5429. Filter dimensions: 16" x 26" x 5". This MERV 16 X5429 filter from Lennox is the best media filtration available short of a HEPA system and does an outstanding job of removing particulates from the air stream, protecting your equipment and your health. The Lennox X5429 MERV 16 filter is a suitable replacement for the Lennox BMAC-14CE air cleaner and it also fits inside the Lennox EAC-12 and EAC-14 cabinets in place of the electronic cells.