FDM seeks to replicate a benchmark which offers exposure to the micro cap sector of the U.S. equity market. The investment thesis behind micro caps is a very similar, but more aggressive approach than small caps. The companies held in this ETF will be very small and volatile firms that have a huge potential for both explosive growth and utter failure. At one point in time most companies were micro caps, and this ETF will give investors exposure to the ones that work their way into the upper echelons of the U.S. equities market. While some exposure to these small companies is healthy for a portfolio, the allocation should be kept low as this ETF will likely exhibit a high amount of volatility as well as being incredibly risky. FDM spreads its assets relatively evenly across numerous market sectors with a slight bias toward financials and consumer stocks. However, this fund has less diversification than other micro cap funds in the field as First Trust employs a 'select' methodology that attempts to weed out some of the worst performers. As a result, this fund will be a good addition for investor looking for growth, but do not mind a bit of risk in their portfolio.