Medal commemorating Lieutenant Otto Hersing and the submarine 'U21'. Obverse: Bust of Lieutenant Hersing in uniform (front) within a laurel wreath. In field: (right) 'U21'; (left) the Order 'Pour le merite' suspended from a laurel branch which forms a border on left and right. Exergue: 'HERSING.' Reverse: Starboard broadside view of a sinking battleship torpedoed amidships, another in the distance, the shore beyond; head of a trident below. Inscription: 'PATHFINDER STR v GIBRALTAR TRIVMPH.' Below: 'MAJESTIC'.