This is a corner mounting accessory for the Motion Detector for Ring Alarm (2nd gen).

The sensor comes with stickers and for most people that is enough, but stickers were not ideal for my walls.

In order to use the holes for corner mounting  already available on the sensor, I would have needed to remove/damage the sticker, which I preferred to avoid.

So, I made this support. I used brass insert nuts (M2, 4mm) and corresponding screws to hold the sensor and the support together.