Strategy. The Fund seeks to track the investment results of the BlackRock Inflation Hedged High Yield Bond Index (the Underlying Index ). The Underlying Index is designed to minimize the inflation risk of a portfolio composed of U.S. dollar-denominated, high yield corporate bonds, which is represented in the Underlying Index by the Underlying Fund, by including a series of up to 10 inflation swap contracts with different maturities (as determined by BlackRock Index Services, LLC (the Index Provider )). As of October 31, 2024, the Underlying Index includes approximately 11 components (including shares of the Underlying Fund), as well as a cash position that is intended to reflect the collateral that must be held to manage the swaps positions. The Fund … Show more… The Fund seeks to track the investment results of the BlackRock Inflation Hedged High Yield Bond Index (the Underlying Index ). The Underlying Index is designed to minimize the inflation risk of a portfolio composed of U.S. dollar-denominated, high yield corporate bonds, which is represented in the Underlying Index by the Underlying Fund, by including a series of up to 10 inflation swap contracts with different maturities (as determined by BlackRock Index Services, LLC (the Index Provider )). As of October 31, 2024, the Underlying Index includes approximately 11 components (including shares of the Underlying Fund), as well as a cash position that is intended to reflect the collateral that must be held to manage the swaps positions. The Fund uses its investment in the Underlying Fund primarily to gain exposure to U.S. dollar-denominated, high yield corporate bonds (commonly referred to as junk bonds ). The Fund seeks to track the inflation hedging component of the Underlying Index primarily through the use of positions in inflation swaps ( i.e ., derivative contracts used to transfer inflation exposure by exchanging a fixed cash flow for a floating cash flow). The Fund makes fixed-rate payments based on a notional reference amount while receiving floating-rate payments on the same notional reference amount determined from an inflation index. The different maturities and weights of the swap contracts included in the Underlying Index are intended to hedge the portfolios inflation exposure at key points on the yield curve, as determined by the Index Provider. The Underlying Index includes a fixed number of shares (to be adjusted in the event of any stock splits) of the Underlying Fund, and the Index Provider rebalances the weights of the swap contracts included in the Underlying Index daily. On a monthly basis, the Index Provider will add new swap contracts to the Underlying Index and remove the previous months swap contracts. The Fund seeks to achieve its investment objective by investing, under normal circumstances, at least 80% of its net assets, plus the amount of any borrowings for investment purposes, in component securities and instruments in the Funds Underlying Index. Cash and cash equivalent investments associated with a derivative position will be treated as part of that position for the purposes of calculating the percentage of investments included in the Underlying Index. The Fund seeks to track the investment results of the Underlying Index before fees and expenses of the Fund. The Fund may also invest in other instruments designed to transfer inflation exposure from one party to another, including but not limited to U.S. Treasury Inflation Protected Securities ( TIPS ), total return swaps, futures and options (collectively with inflation swaps, inflation hedging instruments ). The Funds investments in inflation hedging instruments are not intended to mitigate credit risk or other factors influencing the price of U.S. dollar-denominated, high yield corporate bonds, which may have a greater impact than inflation rates. Moreover, to the extent that inflation exposure has been priced into the U.S. dollar-denominated, high yield corporate bonds owned by the Underlying Fund, the Fund will underperform the Underlying Fund even during inflationary periods. The Commodity Futures Trading Commission ( CFTC ) has adopted certain requirements that subject a registered investment company and its adviser to regulation by the CFTC if the registered investment company invests more than a prescribed level of its net asset value in CFTC-regulated futures, options and swaps, or if the registered investment company markets itself as providing investment exposure to such instruments. Due to the Funds potential use of such instruments above the prescribed levels, it is considered a commodity pool under the Commodity Exchange Act ( CEA ). BFA is considered a commodity pool operator ( CPO ) with respect to the Fund and is subject to regulation by the CFTC and the National Futures Association ( NFA ). BFA uses an indexing approach to try to achieve the Funds investment objective. The Fund does not try to beat the index it tracks and does not seek temporary defensive positions when markets decline or appear overvalued. Indexing may eliminate the chance that the Fund will substantially outperform the Underlying Index but also may reduce some of the risks of active management, such as poor security selection. Indexing seeks to achieve lower costs and better after-tax performance by aiming to keep portfolio turnover low in comparison to actively managed investment companies. BFA uses a representative sampling indexing strategy to manage the Fund and the Underlying Fund. Representative sampling is an indexing strategy that involves investing in a representative sample of securities and/or other instruments that collectively have an investment profile similar to that of an applicable underlying index. The securities ? and/or other instruments selected are expected to have, in the aggregate, investment characteristics (based on factors such as market value and industry weightings), fundamental characteristics (such as return variability, duration ( i.e. , a security's price sensitivity to a change in interest rates), maturity or credit ratings and yield) and liquidity measures similar to those of an applicable underlying index. The Fund or the Underlying Fund may or may not hold all of the securities ? and/or other instruments in the applicable Underlying Index. The Fund may lend securities from its portfolio representing up to one-third of the value of the Fund's total assets (including the value of the collateral received). The Underlying Index is sponsored by the Index Provider, ? an affiliated person of the Fund and of BFA, the Funds investment adviser. The Index Provider determines the composition and relative weightings of the securities in the Underlying Index and publishes information regarding the market value of the Underlying Index. Industry Concentration Policy. The Fund will concentrate its investments ( i.e. , hold 25% or more of its total assets) in a particular industry or group of industries to approximately the same extent that the Underlying Index is concentrated. For purposes of this limitation, securities of the U.S. government (including its agencies and instrumentalities) and repurchase agreements collateralized by U.S. government securities are not considered to be issued by members of any industry. Show less