24" x 24" RETURN FILTER GRILLE for Drop Ceiling - Uses 20" x 20" Filter - Easy Access Door & Latch To Filter Total outer size is made to fit a 24" x 24" drop cieling tile - With Easy Front Access to replace Filter Uses a 20" x 20" filter Carefully shrink wrapped with cardboard backing to prevent damage in shipment Screws Included No Sharp Surface Edges