This is a 3D printed gear wheel to replace the bigger gear of an electric tow hook of the BMW .
There are three gears in the transmission. This is the middle one, so the biggest one and doesn't break that often.
Regarding the installation
The gearhousing can only be opened, if the towhook is in the Retracted Position
When the trailer hook is extended, the housing of the gearbox must be opened as far as possible and pierced with a screwdriver.
Try turning the gears with the screwdriver so that the spindle expands.
Good Luck!