License Plate

All right, i started woring on a license plate from akina, but i dont know how to make it only accepts/generate numbers, not letters, so how do i configure it to only accept numbers?

 

None that I know of. You could make the letters be numbers, but that seems a bit odd.

 

Oh, ok i with that i think i will leave the letters anyways, it will be a bit odd, but at least people can change to numbers