The American Funds Income Series - U.S. Government Securities Fund - Class 529-F-3 (ticker: FSUUX) is a mutual fund that primarily invests in U.S. government securities, such as Treasury bonds and notes. This fund is designed for investors seeking a steady stream of income and a low-risk investment option. It is classified as a Class 529-F-3 fund, which typically indicates a fund that is available for investment through a 529 college savings plan.