Cummins Westport Inc. (CWI) offers heavy-duty natural gas vehicle engines for the automotive market, for applications such as truck and bus. With over 28,000 engines in service worldwide, CWI engines are designed to meet the most stringent emissions regulations and provide efficient and reliable service. Certified with catalyst, they meet or exceed the toughest U.S. Environmental Protection Agency (EPA), California Air Resources Board (CARB), and EURO emissions standards.