Nippon Muki manufactures and sells air filters and clean room products. The company has more than 300 employees and generated sales of ¥8.8 billion in the year to 31 March 2009. Daikin Industries already owns American Air Filter International (AAF) which was acquired in 2007 as part of the OYL Group. Founded in 1921, AAF International is headquartered in Louisville, Kentucky, employs approximately 2600 people and has more than 20 manufacturing facilities worldwide.