12 ga double barrel pat'd number 45120 western arms branch Ithaca gunco inc Ithaca ny?

The 12-gauge double barrel shotgun you mentioned is a product of Western Arms, which was a division of Ithaca Gun Company, known for producing quality firearms in the early to mid-20th century. The patent number 45120 likely pertains to a specific design feature or mechanism of the shotgun. Ithaca, New York, was historically significant for its gun manufacturing, producing a variety of shotguns and rifles. If you're looking for more specific information about this particular model, it may be helpful to consult firearms reference books or collectors' resources.