The iShares 20+ Year Treasury Bond ETF, managed by BlackRock Fund Advisors, is a fund that focuses on long-term U.S. treasury securities. Specifically, it invests in fixed-rate bonds with maturities of over twenty years, aiming to mirror the performance of the ICE U.S. Treasury 20+ Year Bond Index. This ETF offers investors exposure to U.S. government bonds, a cornerstone of fixed income investing. Launched in 2002, it's a way for investors to potentially benefit from the safety and stability of U.S. Treasury bonds.