Use: Indoor Media Air Cleaner for Residential Use Standards: UL, ASHRAE UPC: 8526727701 Part Number: FC40R1011/U The Resideo FC40R1011 Return Grille Media Air Filter is a perfect air purifier that is meant to clean the indoor air by trapping contaminants afloat in the air. Product size is 20” x 25”, with MERV 10 capacity to capture dust. https://www.partshnc.com/fc40r1011-resideo-20x25x3--return-grille-filter