In Windows 10 and Server 2016, WMI added a new property that simplifies collecting chassis or enclosure SKUs. This one-liner reads the SKU for you:
PS> Get-CimInstance -ClassName Win32_ComputerSystem | Select-Object -Property Name, ChassisSKUNumber Name ChassisSKUNumber ---- ---------------- DESKTOP-8DVNI43 Convertible
Whether or not the SKU number is just a generic “Convertible” (for notebooks) or an individual number depends on the manufacturer and BIOS settings.
A more promising class is Win32_SystemEnclosure which is present in all Windows versions:
PS> Get-CimInstance -ClassName Win32_SystemEnclosure | Select-Object -Property Manufacturer, SerialNumber, LockPresent Manufacturer SerialNumber LockPresent ------------ ------------ ----------- Dell Inc. 4ZKM0Z2 False