Affected Products:
Single-Function: C4150, CS720, CS725, CS727, CS728
Multifunction: CX727, XC4143, XC4150, XC4153

Issue Description:
When contacting Lexmark Technical Support or arranging warranty service, you will need to know your printer's machine (model) type and serial number. This article explains how to find information such as the serial number (SN), top-level indicator (TLI), and machine type on the printer.
Locating the Label:

Open the printer's front cover.

Look for a sticker where the information above is located. See the location pointed by the
red arrowon the right-hand image.
NOTE: The printer's serial number is also listed on the menu settings page that you can print using the printer.
LEGACY ID: HO4001