Golf IV: Stamped Numbers in Fender

Hi.
What is the purpose of the numbers that are stamped into the front fenders at the top fold? They are located between the screws that secure the fender at the top.

Thank you and best regards.
Sure, here is the translation of the text from German to English:

'Hati' is a word in the Indonesian language that means 'heart'. It is also a common name in Indonesia.