location of driver-packages downloaded by supportassist

i am on a metered-bandwidth-limited mobile-data. so, i cannot download the driver-packages (especially large drivers) each and every time, i reinstall windows-10. so it would be great if i can store the driver-packages in my external HDD for future use. so, can i know where supportassist stores the driver-packages it downloads? i am asking this because some drivers are available only through supportassist and not in support.dell.com. thanks in advance.