Adb doesn't recognized device

Hi, when I connect my Onyx Nova Pro or Note Pro to my windows machines they are not recognized when I execute "adb devices". On both devices the Usb debugging mode is activated, and the icon of usb debugging appear on the top bar of the eReaders. Fastboot neither works.

Maybe I need some drivers, but I can see the device in the units of my computer as a MTP device and surf through files. Do I need drivers?

Thanks