NUSB holds a diversified portfolio of income-producing fixed income securities, including US Treasurys, government obligations, corporate debt, asset-backed and mortgage-backed securities, and money market instruments. All securities in the fund's portfolio are USD-denominated. The fund seeks to primarily invest in investment grade securities, although it may also have some exposure to junk bonds. It aims to maintain a portfolio duration of one year or less. A significant portion of the fund's assets may be invested in mortgage-backed, mortgage-related, and restricted securities at the adviser's discretion. The fund may utilize futures contracts in hedging various investments, managing risk, and enhancing income. The adviser may also use derivatives to manage yield, interest rate exposure, weighted average maturity, and exposure to credit quality. NUSB is not a money market fund and does not seek to maintain a stable NAV of $1.00 per share.