If you're interested in broad exposure to the Energy - Exploration segment of the equity market, look no further than the iShares U.S. Oil & Gas Exploration & Production ETF (IEO), a passively managed exchange traded fund launched on 05/01/2006.Passively managed ETFs are becoming increasingly popular with institutional as well as retail investors due to their low cost, transparency, flexibility and tax efficiency. They are excellent vehicles for long term investors.Investor-friendly, sector ETFs provide many options to gain low risk and diversified exposure to a broad group of companies in particular sectors. Energy - Exploration is one of the 16 broad Zacks sectors within the Zacks Industry classification. It is currently ranked 7, placing it in top 44%.Index DetailsThe fund is sponsored by Blackrock. It has amassed assets over $274.37 M, making it one of the larger ETFs attempting to match the performance of the Energy - Exploration segment of the equity market. IEO seeks to match the performance of the Dow Jones U.S. Select Oil Exploration & Production Index before fees and expenses.The Dow Jones U.S. Select Oil Exploration & Production Index is a free-float adjusted market capitalization-weighted index. The Index includes companies that are engaged in the exploration for and extraction, production, refining, and supply of oil and gas products.CostsExpense ratios are an important factor in the return of an ETF and in the long term, cheaper funds can significantly outperform their more expensive counterparts, other things remaining the same.Annual operating expenses for this ETF are 0.43%, making it one of the cheaper products in the space.It has a 12-month trailing dividend yield of 1.50%.Sector Exposure and Top HoldingsEven though ETFs offer diversified exposure which minimizes single stock risk, it is still important to look into a fund's holdings before investing. Luckily, most ETFs are very transparent products that disclose their holdings on a daily basis.This ETF has heaviest allocation in the Energy sector--about 100% of the portfolio.Looking at individual holdings, Conocophillips (COP) accounts for about 14.23% of total assets, followed by Eog Resources Inc (EOG) and Marathon Petroleum Corp (MPC).The top 10 holdings account for about 64.56% of total assets under management.Performance and RiskThe ETF has added about 10.71% and is down about -6.47% so far this year and in the past one year (as of 03/14/2019), respectively. IEO has traded between $47.66 and $78.42 during this last 52-week period.The ETF has a beta of 1.34 and standard deviation of 25.55% for the trailing three-year period, making it a high risk choice in the space. With about 65 holdings, it effectively diversifies company-specific risk.AlternativesIShares U.S. Oil & Gas Exploration & Production ETF carries a Zacks ETF Rank of 3 (Hold), which is based on expected asset class return, expense ratio, and momentum, among other factors. Thus, IEO is a good option for those seeking exposure to the Energy ETFs area of the market. Investors might also want to consider some other ETF options in the space.Invesco Dynamic Energy Exploration & Production ETF (PXE) tracks Dynamic Energy Exploration & Production Intellidex Index and the SPDR S&P Oil & Gas Exploration & Production ETF (XOP) tracks S&P Oil & Gas Exploration & Production Select Industry Index. Invesco Dynamic Energy Exploration & Production ETF has $41.77 M in assets, SPDR S&P Oil & Gas Exploration & Production ETF has $1.98 B. PXE has an expense ratio of 0.65% and XOP charges 0.35%.Bottom LineTo learn more about this product and other ETFs, screen for products that match your investment objectives and read articles on latest developments in the ETF investing universe, please visit Zacks ETF Center.Want the latest recommendations from Zacks Investment Research? Today, you can download 7 Best Stocks for the Next 30 Days. Click to get this free report iShares U.S. Oil & Gas Exploration & Production ETF (IEO): ETF Research Reports SPDR S&P Oil & Gas Exploration & Production ETF (XOP): ETF Research Reports Invesco Dynamic Energy Exploration & Production ETF (PXE): ETF Research Reports Marathon Petroleum Corporation (MPC): Free Stock Analysis Report EOG Resources, Inc. (EOG): Free Stock Analysis Report ConocoPhillips (COP): Free Stock Analysis Report To read this article on Zacks.com click here. Zacks Investment Research