This cover commemorates the keel-laying of Submarine, USS Seal on May 25, 1936, from Groton, CT and features a USS Shark SS-314 Submarine hand cancellation marking the event, from the Electric Boat Co, Groton, CT. The cover has a naval theme and is deeply related to World War II, making it a unique addition to any collection. The cancellation is F (Fine) grade and the cover is uncetified. It was manufactured in the United States and is a great representation of naval history. These two submarines served the country honorably. The USS Seal which was commissioned in 1937 received the Asiatic-Pacific Campaign medal with 10 battle stars for World War II service. The USS Shark SS-314 had construction beginning in 1943 and commissioning occurred in 1944. The Shark was deployed to the Pacific where she attacked ships and rescued downed airmen. Shark was sunk on its third patrol by a Japanese destroyer on 24 October 1944. In the engagement in which it was sunk, Shark torpedoed and sank the Japanese freighter Asian Marau. The Arisan Maru was transporting captured Americans but carried no markings or flag indicating this. The Americans had no way of recognizing Arisan Maru was a prison ship.The sinking of Arisan Maru is the greatest loss of American life in a single military sinking. Shark received one battle star for World War II service.