The Lou. Gateway to the West. Mound City. St. Louis has a lot of nicknames. But whatever you call it, you can keep comfortable all year long-especially during the hot, humid summers and the cold winters-by working with Champion on custom-manufactured replacement windows, siding, sunrooms, roofing, and doors. Champion products are made in the USA, and theyre sold, installed, and serviced by professionals in St. Louis who are committed to delivering the finest home-improvement experience possible.