Light years ahead of its time, this rare Tatra is super aerodynamic, sports aluminum body, and by the looks of those generous scoops, is powered by an air-cooled motor sitting over the rear wheels. I'll be checking for more stats and details, and updating this page.
For now check the post between the suicide and rear doors. The thing-y you see is flag style turn signal. When you clicked the lever mounted on the steering column inside the Tatra, the "flag" emerged from its safe keeping. Flag was illuminated and likely flashed, alerting drivers in front and behind of Tatra's intentions.
These signals were used in a number of European cars that I can remember seeing -- models well into late '50's.
My buddy JI had a classic VW bug, "Fritz" by name, and I think his little German (ca 1955) may have had flag signals as well.