(a) The identification plate required to be displayed under 47.101(a) must be etched, stamped, or engraved with the allocated nationality and registration marks.
(b) The identification plate must -
(1) be of fireproof metal or other fireproof material of suitable physical properties; and
(2) be affixed to the aircraft in a prominent position near the main point of entrance to the aircraft.
I thought this was a rather novel way of displaying said ID.