Here are two 12’7 Breda boxes from the Spanish civil war. Both are for ball cartridges, although tracer, API and HE loads were brought into Spain by the Italians. Unfortunately the box top is teared just in the place where it said “MITRAGLIATRICE BREDA”.
The date, i.e. ‘22 APR 1938 Anno XVI’ means April 22, 1938, year 16 of the Fascist Era.
I believe that the R. A. letters on the crest on top of the box stand for “Regia Armata”, Royal Navy. But the wings suggest air service use. In fact this caliber ammunition was used in machine guns on board of Italian planes, delivered to the nationalist side.