The ship 133feet long, with a beam of 24feet. She had a depth of 12feet. She was assessed at, . She was powered by a triple expansion steam engine, which had cylinders of 13inches, NaN0NaN0 and NaN0NaN0 diameter by NaNinches stroke. The engine was built by J. C. Tecklenborg AG., Geestemünde, Germany. It was rated at 55 nhp. It drove a single screw propeller.[1] It could propel the ship at 10kn.
Fritz Reiser was built as yard number 405 by J. C. Tecklenborg AG., Geestemünde, Germany. She was launched on 15 November 1924 and completed on 4 December. Owned by Kämpf & Meyer, her port of registry was Wesermünde. She was allocated the Code Letters KSCF,[1] and the fishing boat registration PG 360. She was sold to the Hochseefischerei Cark Kämpf Partenreederei in 1929. On 6 April 1932, her boilers were damaged at sea, leaving her drifting 80nmi north of the Horns Reef. She radioed of a tow.[2] In 1934, her Code Letters were changed to DEZU.[3]
On 22 September 1939, Fritz Reiser was requisitioned by the Kriegsmarine. Designated as a vorpostenboot. She was allocated to 7 Vorpostenflotille as V 706 Fritz Reiser. On 19 August 1943, she was reallocated to 6 Vorpostenflotille as V 604 Fritz Reiser. In 1944, she was seized at Saint-Nazaire as a prize of war by France. She was sold to the Pool de Lorient. Her port of registry was Lorient, Morbihan and the Code Letters FNFN were allocated.[4] Her name was changed to Le Merlu in 1947. She became a school ship in 1953 and was scrapped in 1954.