Barrel marking include the proof marks, choke code and weight of the barrels. Please be specific and we can give a more direct answer.
Code Letters.
The serial number does NOT contain the date of manufacture on a Benelli (or any Italian-made firearm). You need to look for some "proof-markings," likely along the left side of the barrel beneath where it says, "Benelli Armi SPA Urbino Made in Italy." One of these markings will have two letters enclosed in a box. That is your date code. To figure out to which year your code corresponds, go to the following link: http://unblinkingeye.com/Guns/IDC/idc.html
If you are in the UK, buy a Highway Code from most book shops.
white case with a brown band and black markings
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white case with a brown band and black markings
white case with a brown band and black markings
white case with a brown band and black markings
Color code marking, NSN, lot number nomenclature
The Chicago Code - 2011 Black Hand and the Shotgun Man - 1.7 was released on: USA: 21 March 2011 USA: 21 March 2011
Impossible to answer without a DETAILED description of ALL markings.