Single mount gun sight for the 40mm Bofor’s gun. Not able to test for function. The item “40 MM single barrel gun sight” is in sale since Saturday, September 12, 2020. This item is in the category “Collectibles\Transportation\Boats & Ships\Military\Other Naval Collectibles”. The seller is “lostships” and is located in Des Plaines, Illinois. This item can be shipped to United States.