It looks like it was made for single lines behind a PBX. With sg in the code, it might have been used back in the 336 analog PBX days in Singapore. https://business.panasonic.sg/communication-solutions/kx-t7716

Here in the United States, it probably lacks an FCC registration number....like that matters now :-) In Canada, I don't think the RCMP or CRTC or whoever is going to single you out.

Carl