According to this page (https://thehelm.com/pages/technology), the following is logged.

* Name, address, payment information, domain, DNS records

* Device diagnostics (such as temperature), software versions, enabled services, connection status, connection type, serial number

* Anything related to customer support, including information customers provide

So plenty of information to uniquely identify a system. The last bullet is a little concerning as it seems to be a catch-all.