You can find any tool by the Menu Structure HERE: https://turbocaddoc.atlassian.net/wiki/display/TC20UG/Menu+Structure

You can find the menu location of any tool by name HERE: https://turbocaddoc.atlassian.net/wiki/display/TC20UG/Tools+Mapped+to+Menus

Double Line Properties

Double Lines have unique properties that you can set in the Double Line tab of the Properties window.

Separation: The distance between the lines. If you stretch or scale a double line, this distance does not change. 
End Caps: Closes the endpoints of the double line.
End Cap at End


  
End Cap at Start


Tip: Another way to create end caps is to use the Edit Tool (node editing), right-click on the end node and select Closed Double End.