The ProShares Trust Ultra Short S&P 500 (SDS) is a double inverse ETF meaning that purchasing shares of SDS will give you TWICE the percentage exposure to movements in the S&P 500. If the SPY drops 1%, the SDS moves up 2%, but if SPY is up 1% the SDS should drop 2%. The ProShare funds allow IRAs and other qualified money, which is restricted from marging transactions (which disqualifies short sales) to gain short short exposure by getting long, it also allows for leverage! When the volume swells like it did yesterday is that a contrarian indicator? The 50 day MA is still declining which tells me that the SDS is still in a downtrend and I think that eventually many of those purchasers may regret their decision to buy, they’re probably regretting it already this morning.