The Goodman series of efficiency include single stage, two stage, or multi speed furnaces. Goodman offers multi-position, making them the perfect choice whether you are installing in a basement, closet, or attic. Choose the GMS for upflow/horizontal. The patented aluminized-steel heat exchanger is durable With a Hot Surface Ignition system combined With the heavy-gauge, reinforced, insulated steel cabinet and durable baked enamel finish ensure years of trouble-free performance. Manufactured by Goodman in the U.S.A., you get one of the best warranties in the industry, all at an unbeatable price.