The back part with a tunnel, there are also white plugs for self-tapping screws, I made a special photo with a tape measure for sizes, I made a hole for the hatch along the tunnel (the inner size of the hatch + 5mm) the width of the tunnel is 30-35mm (without a door cover), you can cut it to the desired size
You can now see the product's quality and features in the photos I have added to my review.
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