To maximize income exempt from federal income taxes to the extent consistent with prudent investing and the preservation of shareholders’ capital.

The following table describes the fees and expenses that you will incur if you buy, hold and sell shares of the Fund. You may also incur other fees, such as usual and customary brokerage commissions and other fees to financial intermediaries, which are not reflected in the table and the Example that follows.

This Example is intended to help you compare the cost of investing in the Fund with the cost of investing in other funds. The Example assumes that you invest $10,000 in the Fund for the time periods indicated and then sell all of your shares at the end of the period. The Example also assumes that your investment has a 5% return each year and that the Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based on these assumptions your costs would be:

Under normal market conditions, the Fund invests at least 80% of its net assets in municipal securities whose interest is free from federal income taxes, including the federal alternative minimum tax. Although the Fund tries to invest all of its assets in tax-free securities, it is possible that up to 20% of the Fund’s net assets may be invested in securities that pay interest that may be subject to the federal alternative minimum tax and in securities that pay interest subject to other federal or state income taxes.

In addition, the Fund invests at least 80% of its net assets in municipal green bonds. Municipal “green bonds” are bonds that promote environmental sustainability. The proceeds of green bonds are typically used for one or more of the following purposes: renewable energy, energy efficiency, pollution prevention and control, environmentally sustainable management of living natural resources and land use, terrestrial and aquatic biodiversity conservation, clean transportation, sustainable water and wastewater management, climate change adaptation, eco-efficient and/or circular economy adapted products, production technologies and processes or green buildings that meet regional, national or internationally recognized standards or certifications.

A municipal bond issuer can choose to assign a “green bond” or similar label to its bonds in its offering documents: however, there is no regulation of green bonds as a class and no universal framework for issuing green bonds. In order to determine a green bond’s authenticity, the investment manager completes due diligence on each bond to be purchased to determine whether it meets the “green bond” definition above. After reviewing offering documents and issuer websites, and, if necessary, conferring with the underwriter and issuer, the investment manager places prospective green bonds into one of the following three categories:

· Eligible for investment based exclusively on an internal evaluation of the bond. The investment manager determines that bond proceeds are being issued for environmentally-friendly projects or programs and that the issuer has adequate internal controls and disclosure practices.

· Eligible for investment based on an internal evaluation of the bond as well as an external evaluation by an independent party. The due diligence process is identical, but the investment manager also leverages an independent

evaluation that some issuers engage to verify that the green bond label has been used appropriately to make its determination of authenticity.

· Not eligible for investment. The investment manager places bonds in this category if bond proceeds are not clearly used to promote environmental sustainability, project descriptions are inadequate, or disclosure practices and internal controls are weak.

The investment manager screens all labeled green bonds and bonds with similar labels, but it also will consider bonds with no label for investment by the Fund. The due diligence process and categorization of non-labeled green bonds and labeled green bonds is identical.

The Fund may invest in securities of any maturity or duration. In addition, the Fund may invest in municipal securities issued by U.S. Territories. The Fund does not necessarily focus its investments in a particular state or territory.

The Fund buys predominately municipal securities rated, at the time of purchase, in one of the top four ratings categories by one or more U.S. nationally recognized rating services (or comparable unrated or short-term rated securities). The Fund may hold up to 20% of its net assets in municipal securities rated below investment grade (or comparable unrated or short-term rated securities).

The Fund also may invest in insured municipal securities, municipal lease obligations, variable and floating rate securities (primarily variable rate demand notes), zero coupon securities and deferred interest securities.

Although the investment manager searches for investments across a large number of municipal securities that finance different types of projects, from time to time, based on economic conditions, the Fund may have significant positions in municipal securities that finance similar types of projects.

The investment manager selects securities that it believes will provide the best balance between risk and return within the Fund's range of allowable investments and typically invests with a long-term time horizon. This means it generally holds securities in the Fund's portfolio for income purposes, although the investment manager may sell a security at any time if it believes it could help the Fund meet its goal. With a focus on income, individual securities are considered for purchase or sale based on various factors and considerations, including credit profile, risk, structure, pricing, portfolio impact, duration management, restructuring, opportunistic trading and tax loss harvesting opportunities.

Principal Risks

You could lose money by investing in the Fund. ETF shares are not deposits or obligations of, or guaranteed or endorsed by, any bank, and are not insured by the Federal Deposit Insurance Corporation, the Federal Reserve Board, or any other

agency of the U.S. government. The Fund is subject to the principal risks noted below, any of which may adversely affect the Fund’s net asset value (NAV), trading price, yield, total return and ability to meet its investment goal. Unlike many ETFs, the Fund is not an index-based ETF.

Interest Rate: When interest rates rise, debt security prices generally fall. The opposite is also generally true: debt security prices rise when interest rates fall. Interest rate changes are influenced by a number of factors, including government policy, monetary policy, inflation expectations, perceptions of risk, and supply of and demand for bonds. In general, securities with longer maturities or durations are more sensitive to interest rate changes.

Variable rate securities generally will not increase in market value if interest rates decline. Conversely, the market value may not decline when prevailing interest rates rise. Fixed rate debt securities generally are more sensitive to interest rate changes than variable rate securities.

Liquidity: The trading market for a particular security or type of security or other investments in which the Fund invests may become less liquid or even illiquid. Reduced liquidity will have an adverse impact on the Fund’s ability to sell such securities or other investments when necessary to meet the Fund’s liquidity needs, which may arise or increase in response to a specific economic event or because the investment manager wishes to purchase particular investments or believes that a higher level of liquidity would be advantageous. Reduced liquidity will also generally lower the value of such securities or other investments. Market prices for such securities or other investments may be relatively volatile.

Tax-Exempt Securities: Failure of a municipal security issuer to comply with applicable tax requirements may make income paid thereon taxable, resulting in a decline in the security’s value. In addition, there could be changes in applicable tax laws or tax treatments that reduce or eliminate the current federal income tax exemption on municipal securities or otherwise adversely affect the current federal or state tax status of municipal securities.

States and U.S. Territories: The Fund’s portfolio is generally widely diversified among issuers of municipal securities. However, to the extent that the Fund has exposure from time to time to the municipal securities of a particular state, events in that state may affect the Fund’s investments and performance. These events may include economic or political policy changes, tax base erosion, unfunded pension and healthcare liabilities, constitutional limits on tax increases, budget deficits and other financial difficulties, and changes in the credit ratings assigned to municipal issuers of the state. The same is true of events in U.S. territories, to the extent that the Fund has exposure to any particular territory at a given time.

Municipal Project Focus:  The Fund may invest more than 25% of its assets in municipal securities that finance similar types of projects, such as utilities, hospitals, higher education and transportation. A change that affects one project, such as proposed legislation on the financing of the project, a shortage of the materials needed for the project, or a declining need for the project, would likely affect all similar projects, thereby increasing market risk.

Prepayment: Prepayment risk occurs when a debt security can be repaid in whole or in part prior to the security's maturity and the Fund must reinvest the proceeds it receives, during periods of declining interest rates, in securities that pay a lower rate of interest. Also, if a security has been purchased at a premium, the value of the premium would be lost in the event of prepayment. Prepayments generally increase when interest rates fall.

High-Yield Debt Instruments: Issuers of lower-rated or “high-yield” debt instruments (also known as “junk bonds”) are not as strong financially as those issuing higher credit quality debt instruments. High-yield debt instruments are generally considered predominantly speculative by the applicable rating agencies as their issuers are more likely to encounter financial difficulties because they may be more highly leveraged, or because of other considerations. In addition, high yield debt instruments generally are more vulnerable to changes in the relevant economy, such as a recession or a sustained period of rising interest rates, that could affect their ability to make interest and principal payments when due. The prices of high-yield debt instruments generally fluctuate more than those of higher credit quality. High-yield debt instruments are generally more illiquid (harder to sell) and harder to value.

Bond Insurers: Market conditions or changes to ratings criteria could adversely impact the ratings of municipal bond insurance companies. Downgrades and withdrawal of ratings from municipal bond insurers have substantially limited the availability of insurance sought by municipal bond issuers thereby reducing the supply of insured municipal securities.

Because of the consolidation among municipal bond insurers the Fund is subject to additional risks including the risk that credit risk may be concentrated among fewer insurers and the risk that events involving one or more municipal bond insurers could have a significant adverse effect on the value of the securities insured by an insurer and on the municipal markets as a whole.

Municipal Lease Obligations: Municipal lease obligations differ from other municipal securities because the relevant legislative body must appropriate the money each year to make the lease payments. If the money is not appropriated, the lease may be cancelled without penalty and investors who own the lease obligations may not be paid.

Cybersecurity: Cybersecurity incidents, both intentional and unintentional, may allow an unauthorized party to gain access to Fund assets, Fund or customer data (including private shareholder information), or proprietary information, cause the Fund, the investment manager, authorized participants, or index providers (as applicable) and listing exchanges, and/or their service providers (including, but not limited to, Fund accountants, custodians, sub-custodians, transfer agents and financial intermediaries) to suffer data breaches, data corruption or loss of operational functionality or prevent Fund investors from purchasing, redeeming shares or receiving distributions. The investment manager has limited ability to prevent or mitigate cybersecurity incidents affecting third party service providers, and such third party service providers may have limited indemnification obligations

to the Fund or the investment manager. Cybersecurity incidents may result in financial losses to the Fund and its shareholders, and substantial costs may be incurred in an effort to prevent or mitigate future cybersecurity incidents. Issuers of securities in which the Fund invests are also subject to cybersecurity risks, and the value of these securities could decline if the issuers experience cybersecurity incidents.

Because technology is frequently changing, new ways to carry out cyber attacks are always developing. Therefore, there is a chance that some risks have not been identified or prepared for, or that an attack may not be detected, which puts limitations on the Fund's ability to plan for or respond to a cyber attack. Like other funds and business enterprises, the Fund, the investment manager, and their service providers are subject to the risk of cyber incidents occurring from time to time.

Authorized Participant Concentration: Only an Authorized Participant may engage in creation or redemption transactions directly with the Fund. "Authorized Participants" are broker-dealers that are permitted to create and redeem shares directly with the Fund and who have entered into agreements with the Fund’s distributor. The Fund has a limited number of institutions that act as Authorized Participants. To the extent that these institutions exit the business or are unable to proceed with creation and/or redemption orders with respect to the Fund and no other Authorized Participant is able to step forward to create or redeem Creation Units (as defined below), Fund shares may trade at a discount to NAV and possibly face trading halts and/or delisting. This risk may be more pronounced in volatile markets, potentially where there are significant redemptions in ETFs generally.

Small Fund: When the Fund's size is small, the Fund may experience low trading volume and wide bid-ask spreads. In addition, the Fund may face the risk of being delisted if the Fund does not meet certain conditions of the listing exchange.