Identification Model and Serial Numbers The model number and printer serial number are listed on an identification label located under the top cover on the right side of the printer. The model number is alphanumeric, such as C4253A for the HP LaserJet 4050 N printer. The serial number contains information about the Country of Origin, the Revision Level, the Production Code, and Production Number of the printer. An example of a serial number is USBB123456. The top label also contains power rating and regulatory information as shown in Figure 1-1. Figure 1-1 Sample Label 1-8 Printer Description