Size: 14 x 17 inches

This WWII ‘RESTRICTED’ medium sized poster color identification ship poster is series B-6 and is dated as being issued 2/45. This poster served as an identification tool issued by the Division of Naval Intelligence. The Naval Intelligence Division (NID) was created as a component part of the Admiralty War Staff in 1912. It was the intelligence arm of the British Admiralty before the establishment of a unified Defense Intelligence Staff in 1964. It dealt with matters concerning British naval plans, with the collection of naval intelligence. It was also known as "Room 39", after its room number at the Admiralty.

This poster is titled ‘British Submarines’ and shows some of the most infamous submarine types of WWII including the Fleet type, Seagoing type, and the Coastal type.

Combatants in war have consistently bombed and shot at their own ships and those of their allies, as a result of this friendly fire intelligence resources such as these Naval ID posters and booklet were created to differ friend from foe. While the objective of all seagoing personnel should be to recognize important ships or ship types at a glance, familiarity with the details of naval design illustrated in the following pages may prove of value to the student of ship identification. Determination of a ship's type must constitute a primary step in identification in combat areas. Since accurate estimation of a ship's size is extremely difficult at sea, an observer may have occasion to resort to certain rules of thumb to differentiate various types of fighting ships.