What is this black thing, roughly the size of a coffee mug, cylindrical in shape, attached to a circular bracket, on the side of my neighbours house? Its position can be adjusted, doesn’t light up or make noise. Not sure on weight as it is fixed to the wall. We think that it’s plastic.
Point your phone camera to it when it's dark. See if any light emanations come out of it. Sort of like when you point your camera to your remote controller light.