A. O. Smith Corporation operates through two segments: North America and Rest of World. The Company's Rest of World segment primarily consists of China, Europe and India. Both segments manufacture and market comprehensive lines of residential and commercial gas, gas tankless and electric water heaters, as well as water treatment products. Both segments primarily manufacture and market in their respective regions of the world. Its North America segment manufactures and globally markets specialty commercial water heating equipment, condensing and non-condensing boilers and water systems tanks. It also manufactures and markets in-home air purification products in China. It serves residential and commercial end markets in North America with a range of products, which include water heaters, boilers and other. It supplies water heaters to the residential market in China with a broad product offering, including electric, gas, gas tankless, heat pump and solar units, as well as combi boilers.