It is 9.7 cm (https://www.smarthomeassistent.de/dreame-x40...)

Hello

The X40 is 9.7cm high including the tower! This means it fits under furniture that is 10cm high.

The height is approx. 10cm in normal mode (not raised, e.g. for carpets). As far as I know, it is the deepest in its class)

It's just a Chinese product. They don't think much of giving specifications. The quality in terms of the life cycle of the devices also leaves a lot to be desired. In Asia, they probably only have to give a 1-year warranty, which is roughly how the devices are designed.
BUT: Dreame currently builds the best functioning and smartest mopping robots. I am thrilled with how the X40 cleans and pray that it either survives longer than the last one (1.5 years) or just gives up the ghost again before the warranty expires.
I am not enthusiastic about such quality and waste of resources, but there are no alternatives, the western companies have simply slept through the trend or are simply waiting until the technology is more mature and can then be built into high-quality appliances that last longer