the following sentence:
Both actors involved, the company A and the company B, decide on this basis if the water is boiled
In my understanding, this is a non-defining relative clause as it gives additional information that is not necessary determine which actors are concerned. Then, my textbook says it is necessary to put it in commas and to mention the subject pronoun. This would be something like
Both actors involved, which are the company A and the company B, decide on this basis if the water is boiled
Is my understanding correct?
Thanks for any help!