iShares Dow Jones U.S. Aerospace & Defense Index Fund (the Fund) seeks investment results that correspond generally to the price and yield performance of the Dow Jones U.S. Select Aerospace & Defense Index (the Index). The Index measures the performance of the aerospace and defense sector of the United States equity market. Aerospace companies include manufacturers, assemblers and distributors of aircraft and aircraft parts. Defense companies include producers of components and equipment for the defense industry, such as military aircraft, radar equipment and weapons. The Fund invests at least 90% of its assets in securities of the Index and depositary receipts representing securities of the Index. It may invest the remainder of its assets in securities not included in its Index, futures contracts, options on futures contracts, as well as cash and cash equivalents, including shares of money market funds advised by its advisor. Its investment advisor is BlackRock Fund Advisors.