The MainStay MacKay Total Return Bond Fund, Class R1 (MTMRX) is a mutual fund that focuses on providing investors with a diversified portfolio of fixed-income securities. This fund aims to generate a total return for investors through a combination of income and capital appreciation. It primarily invests in investment-grade bonds, including government, corporate, and mortgage-backed securities. The Class R1 shares of this fund are designed for retirement accounts and have a lower expense ratio compared to other share classes. Overall, MTMRX offers investors a conservative and balanced approach to fixed-income investing.