British tanker Lunula visited the Black Sea according to a letter of the German naval attaché at Istanbul dated 17 February 1940

In his letter dated Istanbul, Turkey 17 February 1940 No. 758 g. reported the German naval attaché to the Oberkommando der Wehrmacht Abteilung Ausland the neutral ships passing Istanbul coming out of the Black Sea and loaded with contraband for or chartered by the enemy. An item reported that the British tanker Lunula was armed with 1 gun and 1 flak at the stern. Hull painted dark grey, funnel and bridge brown.

Source

Bundesarchiv. German Marineattaché for Greece, Romania and Bulgaria 1939-1941. RM 12-II/459.