The MFS Massachusetts Municipal Bond Fund - Class I (MTALX) is a mutual fund that primarily invests in municipal bonds issued by the state of Massachusetts. This fund aims to provide investors with tax-free income by investing in high-quality bonds issued by local governments and agencies within the state. As a Class I fund, it is typically only available to institutional investors and has a lower expense ratio compared to other classes of the same fund. This fund may be suitable for investors seeking a tax-efficient way to generate income while also supporting local infrastructure and development in Massachusetts.