triple proofed 20 gauge with 73mm (?) chambers, based on what appears to be a fairly typical stephanois "propeller" (helice?) mechanism....and action clearly stated as sourced from st. ettienne. history says, company origin in 1932, patented in 1935, built in various conformations, box lock, false side plates, and actual h & h side locks - which the subject gun appears to be. 4 stars would indicate one step below the best grade....and obviously a very nice gun. fab's documents state that the 16 gauge gun with 73mm chambers began "around 1972" - would that be a reference point for the age of the subject gun?
photos are not clear enough to be certain, but i would guess the case colors are cyanide.
i, for one, would love to see a photo or two of the whole gun - to see the stock and general configuration....and learn it's weight and other such information.
best regards,
tom