Launched in 1916, completed in 1917, displacement 260 (surfaced)-400 (submerged) tons, oil-fired internal combustion machinery (surfaced)-electric machinery (submerged) and an armament of 2 torpedo tubes.
Source
Archive Dutch Naval Staff 1886-1942 (National Archive at the Hague, Netherlands) inventory number 155. Fleets (the British Empire and foreign countries) on 1 February 1923.