The Opening Swing Low (OSL) is the lowest point reached by the market as the session opens for trading. This is caused by market orders rushing into the market at open prices. The prices traded on screen during the Opening swing are all market orders. The Opening swing low is independent of time.and is the day’s first auction. It is different from the Opening range which is measured in minutes. Any movement away from the OSL represents a good initiation point, particularly useful in Open drives where the OTF is strong.