NUPAX is a mutual fund that focuses on U.S. equity index put writing strategy. This means that the fund will sell put options on U.S. equity index securities, generating income for investors. The fund is managed by Neuberger Berman, a well-respected investment management firm. As a Class A fund, it may have lower fees and expenses compared to other classes of the same fund. NUPAX offers investors a way to potentially benefit from the performance of the U.S. equity market while also providing a source of income through put writing.