What is the green paint on F1 cars during practice?

Teams may have the greatest minds, latest technology and testing facilities, but nothing is as good as the real thing. When the cars take to the track for practice, this is the chance for the engineers to see how the car or the update performs on the track.

Engineers apply Flow VisA mixture of fluorescent powder and light oil applied to specific areas of the car s body to highlight the... There's more... paint, a mixture of fluorescent powder and light oil to specific areas of the body of the car to highlight the airflow over that area. As the car speeds around the track, the oil dries out leaving a fluorescent ‘tell tail’ on what is really happening with the aerodynamics.