Hello,
in 1916, the German Imperial Navy (Kaiserliche Marine) was looking for a follow up design for the Cöln-class (light) "small" cruisers.
The design was evolved under the name "Flottenkreuzer" (Fleet Cruiser) and was intended to be a high speed reconnaissance cruiser able to make more than 32 knots. Five different versions were ultimately designed by the german engeneers called FK 1, FK 1a, FK 2, FK 3, and FK 4 - none were built.
My drawing depicts the FK 1a with a displacement of 4,850 tons and an armament of five 15 cm SK L/45 (5.9") guns, two 8.8 cm SK L/45 (3.5")anti-aircraft guns and four 60 cm (24 in) torpedo tubes.
Thanks for looking!