The 190RF series are a Return Air Filter Grille used for sidewall or ceiling openings. Our product is constructed to ensure maximum airflow and compliment your home decor. Using our return air filter grille to outfit your ventilation system will improve your home circulation. Product Features: Durable white powder coated, high-quality steel, Removable face allows easy access to replace air filter, accepts a 1 in. filter (not included), 1/2 in. spacing louvers.. High-quality steel construction ensures durability. Designed for openings 20 in. wide by 20 in. long. Suitable for installing in sidewall or ceiling openings. Allows air to flow freely between your ventilation system and a room. Made of high quality steel. White powder coat finish. Removable face allows easy access to replace air filter. Duct opening measurement. Width x height. Accepts a 1 in. filter. Filter not included. Color: Powder Coat White. Color Family: Whites. Installation Location: Ceiling,Wall. Material: Steel. Maximum Duct Opening Length (in.): 20. Maximum Duct Opening Width (in.): 20. Product Weight (lb.): 7.8 lb. Outside Length (in.): 22.75. Outside Width (in.): 22.75