The Level 2 widget is shown by default in Total View when a new Stock tab is opened. 

You can enable or disable the Level 2 widget by using the Level 2 button.

This will show the Level 2 information for the current stock.

The panel offers up-to-date data on the quotes provided by market makers, displaying both the buying and selling prices of a particular stock. Above the Level II view, you'll find a volume bar that indicates recent trades. The height of the bar corresponds to the size of the trade, indicating the position taken.