The Nipro Hachiko Dome (ニプロハチ公ドーム, Nipuro Hachikou Dōmu) is a large wooden stadium in Ōdate, Akita, in northern Japan. The stadium covers an area of 12,915 m2. It was completed in June 1997 and is made from 25,000 Akita cypress trees which are covered with a special double Teflon-coated membrane. This allows enough sunlight into the stadium so that during the day no artificial lights are needed. The stadium is principally used for baseball games, but thanks in part to its removable grandstands, the stadium can also be used for other sports and events.Nipro, a Japanese medical equipment manufacturing company, purchased the naming rights to the dome in 2017.