A similar solution is quite common for other producers and indicates the general concept of low-entry (loosely translated as "vehicle with low starting edge"), respectively.
In the case of the bus SOR BN 12, However, this solution is unique variable height of the roof of the vehicle, popularly known as "hump".
SOR BN 12, thanks to a favorable price became in a relatively short time spread to many small and medium-sized Czech towns.
Due to the special shape of the body is SOR BN 12 very popular for conversion to drive with alternative fuel - compressed natural gas ([CNG]).
Later, it came up with the manufacturer's factory CNG version, known as the SOR BNG 12, which is also equipped with motors Cummins Westport.