An Execution Input block is used to provide input into a Sub-flow. The Execution Input block shows the following properties:
The green out connector in the header is used to define the input execution. So it is to be connected to the first block of the sub-flow which can receive input. Wherever in test the sub-flow will be used, the execution input will be available with the help this block.
The title of the block “Execution Input” can be changed by double-clicking on it and typing in a new title.
Updated January 12th 2018.