This exchange-traded fund (ETF) functions as a "fund of funds," meaning its core strategy is to invest primarily in other, unaffiliated fixed income ETFs that target various fixed income categories. Under typical market circumstances, the fund commits at least 80% of its total assets—including any funds obtained through borrowing for investment—indirectly through these underlying ETFs. These indirect investments are channeled into fixed income securities, as well as derivatives and other financial instruments that replicate the economic features of such securities.