Here are a tremendous pair of cufflinks for history buffs. On the left is the infamous ocean liner RMS Lusitania, which was torpedoed and sunk by a German submarine on May 7, 1915 near the coast of Ireland, killing 1,200 of the nearly 2,000 people aboard the ship. The Lusitania was built by John Brown & Co. of Scotland for the Cunard Line, as were her sister ship on the right, RMS Mauretania, and a third liner (RMS Aquitania). The wartime sinking of the passenger-carrying Lusitania was believed by many to be an illegal act, and hastened the entry of the United States into the Great War. The Mauretania was, at the time of its christening, the largest ocean liner in the world. She set the speed record for an Atlantic Crossing in 1907, a title she held for 22 years. The Mauretania was to serve as a troop transport and hospital ship during the war, and was retired in 1934. These American-made celluloid advertising pinbacks are set in sterling silver bezels and equipped with rotating, T-style silver cufflink posts.