iShares Dow Jones U.S. ETF(AMEX:IYY)

IYY tracks the Dow Jones US Index, which covers 95% of the investable US market. The fund holds well over a thousand names, its broad nature provides solid exposure to the segment. The fund uses a representative sampling index strategy, which means it may not hold all of the exactly underlying stocks of the index but a sample of securities that provide a similar investment profile. At times the fund can present a slight large-cap tilt, but otherwise it's a good representation of the market.