The Fund invests at least 80% of its net assets, plus borrowings for investment purposes (if any), in the constituent securities of the Cboe MLPX ATM BuyWrite Index (the Underlying Index). The Fund's 80% investment policy is non-fundamental and requires 60 days prior written notice to shareholders before it can be changed. The Underlying Index measures the performance of a theoretical portfolio that employs a covered call strategy, as determined by Cboe Global Indices, LLC (Index Provider). A covered call strategy is generally considered to be an investment strategy in which an investor buys a security, and writes (or sells) a call option on that security in an attempt to generate more income. Each time a fund writes a covered call option, the fund receives a payment of money from the investor who buys the option from the fund, which is called the premium. If the fund's value declines because of a decline in the value of a reference index or a reference exchange-traded fund (ETF), the premium that the fund received for writing the covered call option offsets this loss to some extent. The Underlying Indexs covered call strategy provides long exposure to a reference ETF and writes (or sells) covered call options on the reference ETF. Specifically, the Underlying Index holds a theoretical portfolio of the Global X MLP & Energy Infrastructure ETF (the Reference Fund) and writes (or sells) a succession of one-month at-the-money (ATM) covered call options on the Reference Fund. The call options written (sold) by the Fund will be FLexible EXchange (FLEX) options.