The prime of postal vehicle transportation in interwar Czechoslovakia took place in the 1920s. At the beginning a fleet of the new autonomous republic consisted also of vehicles gained from the stock of the defeated Austro-Hungarian army. Since May 1919, likewise some bus lines from Austro-Hungarian era were put into operation and new ones meeting economic and public needs of the young state originated gradually.  A number of postal vehicles increased and transport routes were prolonged. In 1927, Czechoslovak postal vehicle transportation covered 326 vehicles and 2,650 km of routes, which was approximately ten times more than in 1919. Such a positive development was possible predominantly thanks to the reorganisation of postal transportation. In January 1925, Administrative Office of Postal Vehicle Transportation was established and postal transportation offices which secured directly the operation of postal vehicle transportation were founded according to requirements. The motor fleet consisted almost exclusively of products of domestic automotive industry, mainly brands Praga and Laurin & Klement (or more precisely Škoda because since 1925 the automobile plant was taken over by a concern from Plzeň). 
The bus depicted on the postage stamp was manufactured with chassis of Škoda 125 and four-stroke petrol water-cooled four-cylinder engine with capacity of 1,944 cm3 and power of 30 hp. The engine was placed behind the front axle and vehicle transmission consisted of four speeds. The top speed of the bus was 60 km per hour and the fuel consumption ranged from 10 to 15 litres of petrol per 100 km. The bus bodywork was manufactured in a well-known company Sodomka in Vysoké Mýto. Sodomka included bus manufacturing into its programme in 1928 and the very first bus manufactured in this company was produced just with chassis of Škoda 125. Until 1933, the company manufactured approximately 35 buses in various modifications, for instance: a fire bus or excursion bus with open roof for spa town guests. A postman wearing a period postal uniform with a leaving bus Škoda 125 in the background is depicted on FDC.
                                                                                                                                                                                      Leo Lichvár