The tblk device has an associated label (defaulting to the device name) which can be changed by the user by selecting the label and pressing the label button in the side menu. All nodes connected to a terminal device with the same label are taken as being connected together. The label of the terminal device is also used to name the node in netlist output.
This is functionally identical to and can be freely intermixed with tbar terminals, the only difference is visual appearance.