Fixed-income investors who like a more hands on approach in managing their bond investments can take a look at two new iShares municipal bond exchange traded funds that could fit well in a laddered portfolio strategy.

BlackRock’s iShares recently launched the iBonds Dec 2021 AMT-Free Muni Bond ETF (NYSEArca: IBMJ) and the iBonds Dec 2022 AMT-Free Muni Bond ETF (NYSEArca: IBMK) on the heels of the closure of the iBonds Sep 2015 AMT-Free Muni Bond ETF (NYSEArca: IBMD).

According to iShares, IBMD closed on September 1 in accordance with its prospectus and investment objective. Investors will receive the entire amount of their proceeds in cash on or after September 8.

These defined-maturity bond funds typically buy bonds that mature in the year the ETF will terminate, ensuring that investors can collect the bonds’ face value at maturity, along with a steady income stream along the way. As such, investors are meant to buy-and-hold these securities until maturity. In contrast, a regular bond ETF runs the risk of losing its original principal if interest rates go up, depending on the bond ETF’s effective duration, since the bond funds would buy and sell debt securities to maintain their target strategy.

Using target-date bond funds, an investor could create a bond ladder strategy to create a portfolio with varying maturity dates. The bonds’ maturity dates are evenly spaced across several years so that the proceeds from maturing bonds may be reinvested at regular intervals, so those investors who held IBMD upon maturity can turn around and reinvest the money back into IBMJ if they already hold position in the other target-date muni bond ETFs.

The iShares iBond suite also includes the iBonds Sep 2016 AMT-Free Muni Bond ETF (NYSEArca: IBME), iBonds Sep 2017 AMT-Free Muni Bond ETF (NYSEArca: IBMF), iBonds Sep 2018 AMT-Free Muni Bond ETF (NYSEArca: IBMG), iBonds Sep 2019 AMT-Free Muni Bond ETF (NYSEArca: IBMH) and iBonds Sep 2020 AMT-Free Muni Bond ETF (NYSEArca: IBMI).