RFG is a growth-oriented mid-cap ETF picking companies in the S&P 400 based on sales growth, price-to-earnings growth, and momentum. It then weights them according to these growth characteristics. The Pure name claim comes from the fact that it excludes securities showing value characteristics and those in the middle of the growth-value spectrum, it chooses strictly growth stocks. Ultimately, RFG aims to provide a pure-style take on mid-cap growth companies. The Fund and the Index are rebalanced annually.