As his chauffeur Kempka usually drove one of Hitler's black Mercedes cars from a fleet of six to eight that were stationed in Berlin, Munich and other places. Unless in the company of an important person, Hitler would sit in the front, next to Kempka, with a valet behind him. When travelling in motorcades, Hitler's car would be followed by two cars to the left and right, one with FBK men and the other with a detachment of "Reichssicherheitsdienst" (Reich Security Service; RSD) men. Further behind would be a car with his adjutants and physician, and more cars for press agency representatives, stenographers, and provisions. Later in July 1938, upon Kempka's directive a fully armor-plated Mercedes was built and delivered in time for Hitler's 50th birthday of 20 April 1939. The car had 18 mm steel plate and 40 mm bullet-proof glass.