A Blaupunkt (or Bosch) serial number is 14 characters long, prefixed with either BP or CM and is usually on the main label, although sometimes it could be stamped on the side.
Optional: Although the Part Number is optional, it can be useful in certain situations. It is a 10 digit number in the format 7 000 000 000. Sometimes two part numbers will be listed, in which case choose the one marked BP Part Nr.
Serial Number: BP237534082298
Part Number: 7642375316
Serial Number: CM0333D0333333
Part Number: 7640333316