Barclays MBS Bond Fund

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Carefully consider the iShares Funds' investment objectives, risk factors, and charges and expenses before investing. This and other information can be found in the Funds' prospectuses, which may be obtained by calling 1-800-iShares (1-800-474-2737), or by viewing or downloading a prospectus. Read the prospectus carefully before investing.

Investing involves risk, including possible loss of principal.

‡ “Acquired Fund Fees and Expenses” reflect the Fund's pro rata share of the indirect fees and expenses incurred by investing in one or more acquired funds, such as mutual funds, business development companies, or other pooled investment vehicles. Acquired Fund Fees and Expenses are reflected in the prices of the acquired funds and thus included in the total returns of the Fund.

† The total annual operating expenses of the iShares Barclays Aggregate Bond Fund and iShares Barclays MBS Bond Fund include “acquired fund fees and expenses” which are related to the funds' investments in the BlackRock Cash Funds: Prime (the “money market fund”). “Acquired fund fees and expenses” represent the funds' pro rata share of the fees and expenses charged by the money market fund and may vary based on the funds' allocation of assets to the annualized net expenses of the money market fund. Annual operating expenses do not include the effect of interest earned by investments in the money market fund, which is expected to offset the money market fund's fees and expenses.

The iShares Funds ("Funds") are distributed by SEI Investments Distribution Co. ("SEI"). BlackRock Fund Advisors ("BFA") serves as the investment advisor to the Funds. BFA is a subsidiary of BlackRock Institutional Trust Company, N.A., neither of which is affiliated with SEI.

Bonds and bond funds generally decrease in value as interest rates rise. Mortgage-backed securities are subject to prepayment and extension risk and therefore react differently to changes in interest rates than other bonds. Small movements in interest rates may quickly and significantly reduce the value of certain mortgage-backed securities.

Index returns are for illustrative purposes only and do not represent actual iShares performance. Index performance returns do not reflect any management fees, transaction costs or expenses. Indexes are unmanaged and one cannot invest directly in an index. Past performance does not guarantee future results.

The iShares Funds are not sponsored, endorsed or issued by Barclays Capital. This company does not make any representation regarding the advisability of investing in the Funds. Neither SEI, nor BlackRock Institutional Trust Company, N.A., nor any of their affiliates, are affiliated with the company listed above.

Shares of iShares Funds are bought and sold at market price (not NAV) and are not individually redeemed from the Fund. Brokerage commissions will reduce returns.

Certain sectors and markets perform exceptionally well based on current market conditions and iShares funds can benefit from that performance. Achieving such exceptional returns involves the risk of volatility and investors should not expect that such results will be repeated.

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