I was able to google the panels via the part numbers on the case. They came in a few different colours and were used for recognition by friendlies in the air. They could be on vehicles, but were also used for drop zone indication. I saw red and yellow at the store, but I think there was another colour there as well.
Here is a lonk to more info on the panels:
http://www.airborne101st.com/pathfinders.html