Coloured no.plates

[garycab]

Passed a car going in the opposite direction today, front and back no.plates were green in colour with yellow letters/digits, never seen one before, any ideas where the car was from ?

[Max M4X WW]

Like these?

http://www.olavsplates.com/benin.html

[garycab]

That's the ones , never heard of it !!
Thanks.