TLT invests in U.S. Treasuries with 20+ year maturities, offering an attractive 4.73% yield but very high interest-rate sensitivity (duration). Its -7.2% one-year return and -10.3% max drawdown are the worst among the bond ETFs in this batch.

It tends to rally during recessions given its low correlation with stocks, but can suffer larger losses in a rising- or high-rate environment like the current one. It's the most extreme illustration of the bond-investing principle that longer maturities mean higher yield but also greater price swings.