Sustainability and innovation have been key words throughout the 120 year history of A.O. Smith. As the inventor of a patented glass coating process, A.O. Smith knows like no other how to maximize the lifetime and quality of glass lined-steel water heating appliances. A.O. Smith offers a wide range of water heaters. Through constant innovation, at production level and application level, A.O. Smith maintains its leading position in the market. This applies both to the choice of materials and components used in the manufacturing process, as well as to the efficiency of the finished products.