AAON, Inc. engineers, manufactures and markets air-conditioning and heating equipment consisting of rooftop units, chillers, air-handling units, condensing units and coils. The Company's products serve the commercial and industrial new construction and replacement markets. The rooftop and condenser markets consist of units installed on commercial or industrial structures of generally less than 10 stories in height. Air-handling units, chillers and coils are applicable to all sizes of commercial and industrial buildings.