When the car in the front breaks, the smart also brakes with its recuperation. It recovers energy and thus drives even more efficiently.
This function is standard from the Passion equipment and turned on by default. If you prefer to one pedal drive, you can simply switch off the radar based regen on the instrument cluster. This does not affect the break assistant.
Some of you might already know it from other EQ models. Daimler also likes to refer to it as "ECO Assistent".
The radar based regen is only available in Europe.