Launched on 11/01/2006, the Invesco S&P 500 Equal Weight Materials ETF (RTM) is a smart beta exchange traded fund offering broad exposure to the Materials ETFs category of the market.What Are Smart Beta ETFs?For a long time now, the ETF industry has been flooded with products based on market capitalization weighted indexes, which are designed to represent the broader market or a particular market segment.Investors who believe in market efficiency should consider market cap indexes, as they replicate market returns in a low-cost, convenient, and transparent way.If you're the kind of investor who would rather try and beat the market through good stock selection, then smart beta funds are your best choice; this fund class is known for tracking non-cap weighted strategies.These indexes attempt to select stocks that have better chances of risk-return performance, based on certain fundamental characteristics or a combination of such characteristics.Even though this space provides many choices to investors--think one of the simplest methodologies like equal-weighting and more complicated ones like fundamental and volatility/momentum based weighting--not all have been able to deliver first-rate results.Fund Sponsor & IndexManaged by Invesco, RTM has amassed assets over $477.80 million, making it one of the average sized ETFs in the Materials ETFs. This particular fund, before fees and expenses, seeks to match the performance of the S&P 500 Equal Weight Materials Index.The S&P 500 Equal Weight Materials Index equally weights stocks in the materials sector of the S&P 500 Index.Cost & Other ExpensesSince cheaper funds tend to produce better results than more expensive funds, assuming all other factors remain equal, it is important for investors to pay attention to an ETF's expense ratio.Operating expenses on an annual basis are 0.40% for this ETF, which makes it one of the cheaper products in the space.RTM's 12-month trailing dividend yield is 1.47%.Sector Exposure and Top HoldingsWhile ETFs offer diversified exposure, which minimizes single stock risk, a deep look into a fund's holdings is a valuable exercise. And, most ETFs are very transparent products that disclose their holdings on a daily basis.Representing 100% of the portfolio, the fund has heaviest allocation to the Materials sector.When you look at individual holdings, Mosaic Co/the (MOS) accounts for about 4.59% of the fund's total assets, followed by Cf Industries Holdings Inc (CF) and Air Products And Chemicals Inc (APD).Its top 10 holdings account for approximately 38.85% of RTM's total assets under management.Performance and RiskYear-to-date, the Invesco S&P 500 Equal Weight Materials ETF has lost about -1.88% so far, and is up about 13.26% over the last 12 months (as of 03/16/2022). RTM has traded between $149.81 and $180.89 in this past 52-week period.The ETF has a beta of 1.09 and standard deviation of 27.99% for the trailing three-year period, making it a medium risk choice in the space. With about 29 holdings, it has more concentrated exposure than peers.AlternativesInvesco S&P 500 Equal Weight Materials ETF is a reasonable option for investors seeking to outperform the Materials ETFs segment of the market. However, there are other ETFs in the space which investors could consider.Materials Select Sector SPDR ETF (XLB) tracks Materials Select Sector Index and the FlexShares Morningstar Global Upstream Natural Resources ETF (GUNR) tracks Morningstar Global Upstream Natural Resources Index. Materials Select Sector SPDR ETF has $7.02 billion in assets, FlexShares Morningstar Global Upstream Natural Resources ETF has $7.57 billion. XLB has an expense ratio of 0.10% and GUNR charges 0.46%.Investors looking for cheaper and lower-risk options should consider traditional market cap weighted ETFs that aim to match the returns of the Materials ETFs.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 key ETF info delivered straight to your inbox? Zacks’ free Fund Newsletter will brief you on top news and analysis, as well as top-performing ETFs, each week.Get it free >>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 Invesco S&P 500 Equal Weight Materials ETF (RTM): ETF Research Reports Air Products and Chemicals, Inc. (APD): Free Stock Analysis Report CF Industries Holdings, Inc. (CF): Free Stock Analysis Report The Mosaic Company (MOS): Free Stock Analysis Report Materials Select Sector SPDR ETF (XLB): ETF Research Reports FlexShares Morningstar Global Upstream Natural Resources ETF (GUNR): ETF Research Reports To read this article on Zacks.com click here. Zacks Investment Research