Please patronize No customer

I still could not figure out how I can open the device if necessary. In the previous model that was possible and I was thus able to establish beyond doubt that it was a fraction of a gear and thus (for lack of availability of spare parts) a new device is required. I am a doctorate in engineering and would not like to be patronized. When I open such a device, I know what dangers involves and how I should conduct myself so that nothing "happened". Therefore, I have only awarded 3 points here.