The iShares U.S. Aggregate Bond Index Fund - Institutional (BMOIX) is a mutual fund that seeks to track the performance of the U.S. investment-grade bond market. It is designed for institutional investors and offers a diversified portfolio of high-quality bonds, providing potential for income and stability in a well-rounded investment strategy. BMOIX is managed by iShares, a leading provider of exchange-traded funds (ETFs) and other investment products.