What's the number on the glass?

Zitat (polski, 29.01.2022):
> What's the number on the glass?

It's a 4

I'm talking about 240.
What does that mean?)

Zitat (polski, 29.01.2022):
> I'm talking about 240.
> What does that mean?)

I don’t really know.. I’m sry

That should be the plan / course number.
This is also used by some other companies like KVG Stade for the clear identification when several vehicles drive with different destinations on the same line. So especially in school transport the younger school kids get on the right bus at schools where many buses arrive at once.