The Default Quantity Override is a feature available on the Market Maker and Market Depth windows. The default quantity override value will override the default order quantity specified on the settings window - something tab and the default speed key quantity.
The default quantity and speed key quantity can be overridden by the Quantity Override feature. A Quantity Override is a feature in the Market Maker and Market Depth windows. It can be set by hitting the '\' key, typing a number and hitting enter. It can be disabled by hitting the '\' key and then enter without typing any digits or by right-clicking on a Market Maker or Market Depth windows and clearing the "Enable quantity override" option. To re-enable the override, simply reenter a number or check the "Enable quantity override" option. Initial value for the quantity override is the default order entry quantity. It is reset every time a new symbol is entered into the Market Maker or Market Depth window. Optionally, it can also be reset to the default after every Order Request by checking the "Reset Quantity on Order Load/Placement" option.
A Quantity Override is a feature of the Market Maker and Market Depth function windows.
You can set a default quantity in the Market Maker window by pressing the '\' key, typing a default quantity, and then pressing Enter.
It can be disabled by hitting the '\' key and then pressing Enter.
To enable the quantity override feature, perform the following from the Market Maker or Market Depth window:
Press the backslash "\"
key. The Quantity pop-up appears.

Type the new default quantity
and press Enter. The new default quantity appears when you place an order.
NOTE: When you enter a default quantity, the Enable
Quantity Override option will automatically enable so the system
can use the new default value.
To disable the quantity override feature, perform one of the following from the Market Maker or Market Depth windows to disable Quantity Override:
Press the '\' key and then press Enter (without typing any digits)
Right-click to view the pop-up menu and then click "Enable quantity override" to clear the check mark