The MainStay MacKay California Tax Free Opportunities Fund, Class I (MCOIX) is a mutual fund that focuses on investing in tax-free municipal bonds issued by the state of California. This fund aims to provide investors with a steady stream of tax-free income while also seeking to preserve capital. 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. MCOIX is managed by MainStay Investments and MacKay Municipal Managers, and may be a suitable option for investors seeking tax-free income from California municipal bonds.