The MFS High Income Fund Class R4 (MHIJX) is a mutual fund that focuses on generating high levels of income for investors. It primarily invests in a diverse portfolio of fixed-income securities, such as corporate bonds, government bonds, and mortgage-backed securities. This fund is designed for investors seeking a steady stream of income, with a moderate level of risk. It is managed by MFS Investment Management, a well-respected asset management company with a long history of successful fund management. The Class R4 shares of this fund have a lower expense ratio compared to other share classes, making it an attractive option for investors looking to maximize their returns.