Problem

You would like to find out the exact model from your Thinkpad X1 laptop, by using your linux command line.

Solution

Use the following command:

kosmas:$ sudo dmidecode | grep -A3 '^System Information'
[sudo] password for kosmas: 
System Information
        Manufacturer: LENOVO
        Product Name: 20HRCTO1WW
        Version: ThinkPad X1 Carbon 5th