Use this function to attach a serial number to a part. This requires that the part has no serial number already attached, which requires that the Inventory Serial Tracking flag is not set; additionally, it requires that the flag After Delivery Serial Tracking is set. If none or both flags is set, you cannot set the serial number. The flags are handled in Part. The serial number gives you the tool to keep track of one specific instance of a part. To set the serial number, use the menu option Serials and click on Set Serial. Set serial number can be performed on parts after they are issued to the project, and the parts cannot have serial numbers in Inventory. This is the case, for example, if you record the serial numbers on the plant after assembly and you want to keep track of that information.