The investment seeks to track the investment results of the S&P AMT-Free Municipal Series Callable-Adjusted Dec 2026 IndexTM composed of investment-grade U.S. municipal bonds expected to mature or be redeemed before December 2, 2026. The fund generally will invest at least 90% of its assets in the component securities of the underlying index, except during the last months of the fund's operations, and may invest up to 10% of its assets in certain futures, options and swap contracts, cash and cash equivalents. It is non-diversified.