Software:
Unreal Engine 4.18
UE4 Material Blueprint Numerical Vector Parameters / Constants and Colors are one and the same, which makes perfects sense, since in computer graphics colors are in fact 3D vectors, RGB quantities being equivalent to XYZ spatial dimensions (4D with an Alpha channel)
But take note that when setting the Vector values in the color picker you can’t set negative values, and when doing so through the Details window in Default Value you can.
* You can create 3D Vector Constants by clicking the background while pressing 3
