You recognize the number
FIG 398 from somewhere?
It's the no. of the licens plate of one of the trucks in the Black Death track.
So what's with that? A sign with fig on it, a fig sign.

If you know your slavic culture then you know what the fig sign is.
From wikipedia:
"...
fig sign, is a rude gesture used in Slavic culture and some other cultures that uses two fingers and a thumb, but not equal to the finger in Anglo-American culture."
Now I just need Raaids help to find out what the number 398 stands for.