The facelifted four-cylinder cars 180 b/180 Db (W 120) and 190 b/190 Db (W 121) and the newly developed luxury models 220 b, 220 Sb and 220 SEb (W 111) celebrate their premiere at the International Motor Show in Frankfurt am Main. The "b" in the model designation is only used internally and serves to distinguish the new models from the preceding ones. All new car models have interior appointments designed to avoid or reduce injuries in accidents. In the "fintail body" of the six-cylinder models, the safety cell with crumple zones originally conceived by Béla Barényi is featured for the first time in a series-produced passenger car. Also making its debut appearance is the Mercedes-Benz O 322 urban bus with rear-mounted engine and air suspension.