"If you look at some of the more market-cap-weighted-oriented products in exploration and production like IEO, which is heavily weighted towards ConocoPhillips and EOG Resources, those are companies that have much stronger balance sheets that are likely to survive the volatility that we're seeing within the oil markets than these smaller companies," Rosenbluth said. IEO is the iShares U.S. Oil & Gas Exploration & Production ETF. ConocoPhillips and EOG together account for nearly 27% of its overall holdings.