I'm not sure how old this bottle is. On the bottom of the bottle it is marked as 337ml into the glass. The front label says it is 11.4 fluid oz and it was imported into New York N.Y. from guiness harp Corp. It is a guiness extra stout NOT a guiness foreign extra stout.
I have a old guiness bottle I acquired from my grandfather and the code is L/A1 911212 and it still has the original guiness in it. Where do I go to find out more info on this? Thx Brian