An auction order is entered into the electronic trading system during the pre-market opening period for execution at the Calculated Opening Price (COP). If your order is not filled on the open, the order is re-submitted as a limit order with the limit price set to the COP or the best bid/ask after the market opens.
The Reference Table to the upper right provides a general summary of the order type characteristics. The checked features are applicable in some combination, but do not necessarily work in conjunction with all other checked features. For example, if Options and Stocks, US and Non-US, and Smart and Directed are all checked, it does not follow that all US and Non-US Smart and direct-routed stocks support the order type. It may be the case that only Smart-routed US Stocks, direct-routed Non-US stocks and Smart-routed US Options are supported.
You want to buy 10 XYZ futures contracts as an auction order at the calculated opening price, which you think will be the best price of the day. Create a buy order row, and selected MTL as the Type and AUC as the time in force. The market to limit order type with the AUC time in force define your order as an auction order. The order will be converted to a limit order at the Calculated Opening Price if it is not filled during the pre-market opening period.