Low-cost “core” exchange traded funds are helping BlackRock’s (NYSE: BLK) iShares unit, the world’s largest ETF issuer, attract billions of dollars of new assets from cost-conscious retail investors.

“The second quarter was very strong for the ETF industry as more and more investors embraced ETFs, and iShares ETFs specifically, for low-cost, diversified access to global markets,” Patrick Dunne, head of iShares Global Markets and Investments at BlackRock, said in an Investor’s Business Daily article.

For instance, the fund provider’s line of Core ETFs come with annual fees ranging from 0.09% to 0.15% – lower than the typical iShares fund. [Investors Gravitating to Cheaper iShares ‘Core’ ETFs]

Additionally, the low-cost theme also translated well over on the investment execution side as iShares saw increased assets through its partnership with Fidelity.

“Our partnership with Fidelity is another important aspect of our retail strategy,” Dunne said. “The outsized growth we’ve seen in our commission-free iShares funds at Fidelity, coupled with the increase in Fidelity accounts holding our funds, speaks to how our growing partnership is resonating with retail investors.”

Building on its success, iShares recently added 10 new Core funds to help investors lay a bedrock for their portfolio positions. Dunne points out that investors are increasingly turning to iShares Core ETFs as long-term strategic positions for their portfolios. [iShares to Make Significant Additions to Core Lineup]