You can see the mounting part in the pictures at the Amazon site but that is not the place to buy one if you just want the rear camera, B&H Camera sells it for $100, far below the $170 on Amazon (not a surprise to me!). There aren't any reviews on Amazon, just two promos on YouTube. The same comment above about the rear camera failure is in the review column at B&H where it also has a better picture of the mount. At some point B&H was selling it for $70 Look at the customer reviews for pictures of the camera mounted on the seatppost.
https://www.bhphotovideo.com/c/produ...bike_dash.html