Comprises 4 monochrome photographs, mounted on card, and one sheet of tracing paper with hand-drawn plans, elevation and section for Otto Koenigsberger's extension to a summer house in Usedom, Pomerania, designed in 1930 for the Mass family. Photographer unknown. The drawings are signed and dated by Koenigsberger and bear the perforated stamp of the Berlin Technische Hochschule, indicating the project was also used as part of his architectural studies. Also included is an envelope labelled 'Karlshagen Negatives' containing 7 monochrome photographic negatives and 2 thumbnail monochrome  photographic prints.