Definition of identical / like for like

Hey folks,
I am currently updating quality procedures and I need to define “Identical” equipment. I am purposely avoiding trying to define “equivalence” as that is a windy road that I do not wish to defend in an audit situation.

I would consider equipment to be identical if it has the same make, model and settings. Is there anything else I should consider, to nail something down as identical? Basically this will be the foundations for allowing me to IQ all equipment and leverage the OQ (and perhaps some elements of PQ) for all subsequent “identical” equipment.