List any specs that you can find out about the driver, whether obtained by yourself or already given by the manufacturer. The measurements can be approximate, just round off to your unit of choice. Also, if the driver has any sort of identification markings on it, list those too.
driver type - dynamic
from headphone brand and model - AKG K240M
driver diameter (or L x W if square shaped) - ~1.25" (~32mm)
driver depth -
diaphragm thickness -
impedance - 600 ohms
markings on back - 10WD