iShares U.S. Utilities ETF(AMEX:IDU)

IDU holds a float-adjusted market-cap-weighted portfolio of large-cap US utilities firms. The funds advisor uses a representative sampling approach to indexing, meaning the fund may not hold all of the underlying in the index but a sample of securities that provide the same investment profile. Regulatory capping targets are also applied at each quarterly rebalance such that single issuer weights are capped at 22.5% and the aggregate weight of all companies exceeding 4.5% weight is capped at 45%. Additionally, the fund may hold cash and cash equivalents, money market funds, and derivatives including futures, options and swap contracts up to 20% of the portfolio to maximize investment. In all, it's a good choice for investors looking for a diversified, broad exposure to the segment. Prior to September 20, 2021, the fund tracked the Dow Jones U.S. Utilities Index.