MZZ provides daily geared inverse (-2x) exposure to the S&P mid-cap 400 Index. The underlying index is market cap-weighted, comprises 400 US mid-cap companies in a variety of sectors, and factors in criteria such as liquidity, price, market capitalization and financial viability. Its a leveraged version of MYY, which seeks -1x exposure to the same index. As a levered product, MZZ presents different risks than other types of funds and is thus not a buy-and-hold investment. It should not be expected to provide index leverage returns greater than a one-day period.