Find the serial number on your Microsoft or Surface device
https://support.microsoft.com/en-us/surface/find-the-serial-number-on-your-microsoft-or-surface-device-6c0abc0c-2b45-247d-f959-70e504e55fa5
WEBIn Settings, tap About > Model & hardware, and look for your Serial number. This is the quickest way to find your serial number. However, if your Surface Duo doesn’t turn on, you can also find the serial number on the SIM card tray after you eject it. See the following section for details.
DA: 12 PA: 4 MOZ Rank: 48