You can find the exact dimensions here:
Technical data > Infographic
https://www.bequiet.com/de...
To be able to read the figures: possibly copy the image and enlarge it with the PowerPoint programme.

Note that the dimensions are with an external fan, if a third fan is fitted, the whole thing will be about 26 mm WIDER / LONGER.
"DOUBLE-TOWER CONSTRUCTION
Powerful cooling of components
The Dark Rock Pro 4 has two aluminium heat sinks. Recesses on the cooling fins increase RAM compatibility. For exceptional cooling requirements, there is the option to add an additional 120mm fan to the two pre-installed fans."
https://www.bequiet.com/de...