Coastlines CL-UWH01 Underwater Hull, Derfflinger class 1/1250
To fit 1/1250 scale Derfflinger class battlecruisers, Hindenburg, Luetzow and Derfflinger, when displayed in a drydock.
This model was designed some years ago and is a slightly better fit under original Navis models without torpedo nets (as in the photograph) than it is on the newer "N" models. The propellers have been omitted to allow the model to sit flat in a model drydock.