Installation of external screen   Device version: every 4.x.x VIDEO TUTORIAL     DESCRIPTION After unwrapping the device, unlock the fixtures which are placed  on the bottom of the screen on each side of the screen. It requires unscrewing the safety screws. Push the screen to the vertical position and close the safety locks. This is a very important step so please double check if you close the locks. They are placed inside the device, one on the left and one on the right side. You have to hook the clips on the safety bolt.