ZF Friedrichshafen AG, also known as ZF Group, originally Zahnradfabrik Friedrichshafen, and commonly abbreviated to ZF (ZF = "Zahnradfabrik" = "Cogwheel Factory"), is a car parts maker headquartered in Friedrichshafen, in the south-west German state of Baden-Württemberg and Livonia, Michigan, United States. Specialising in engineering, it is primarily known for its design, research and development, and manufacturing activities in the automotive industry. It is a worldwide supplier of driveline and chassis technology for cars and commercial vehicles, along with specialist plant equipment such as construction equipment. It is also involved in rail, marine, defense and aviation industries, as well as general industrial applications. ZF has 241 production locations in 41 countries with approximately 148,000 (2019) employees.