Biber was a German midget submarine of the Second World War. Armed with two externally mounted 53-centimetre (21 in) torpedoes or mines, they were intended to attack coastal shipping. They were among the smallest submarines in the Kriegsmarine.
Example on display at Technikmuseum Speyer, Germany
The instruments and controls of a Biber submarine
The propeller and wooden control surfaces
A Biber captured by the British Army near Arras, France, after being abandoned by the retreating Germans (1944)
A midget submarine is any submarine under 150 tons, typically operated by a crew of one or two but sometimes up to six or nine, with little or no on-board living accommodation. They normally work with mother ships, from which they are launched and recovered and which provide living accommodation for the crew and support staff.
Some 80 Japanese Type D ("Koryu") Midget Submarines in a dry dock at Kure, 19 October 1945
Crew of a British X-class midget submarine, part of the British Pacific Submarine Fleet
German midget submarine Seehund, with a torpedo
An Italian CB-class submarine in the Nikola Tesla Technical Museum in Zagreb, Croatia