This value reports (and may be set for override purposes) the Mobile Country Code (MCC), with -1 meaning "Not Applicable." An admin uses this numeric country identifier, alongside the mobile network code, to precisely identify the specific carrier network the device has registered on, more rigorously than the human-readable country string. For example, an admin scripting automated monitoring across many international sites would use this numeric MCC value to programmatically flag any device registered under an unexpected country code.