PowerShares Senior Loan Portfolio (NYSEArca: BKLN) is one of the best-selling ETFs in the first quarter with inflows of more than $1.4 billion. Investors have flocked to the fund in search of decent yields and protection from rising interest rates.

The ETF’s inflows are notable for a fund with just under $3 billion in assets under management.

BKLN is appropriate for investors who are willing to take on additional credit risk and who may be looking for floating-rate bonds to protect against rising interest rates, says Morningstar analyst Timothy Strauts.

“Bank loans are denoted ‘high yield’ in large part because the firms issuing them are highly leveraged,” he writes in a profile of the ETF. “Most investors typically become interested in bank loans when interest rates are expected to rise.”

BKLN has a distribution yield of 4.59%, according to manager Invesco PowerShares. The ETF has an expense ratio of 0.66%.

Another ETF tracking the sector is the Highland/iBoxx Senior Loan ETF (NYSEArca: SNLN). [Bank Loan ETFs]