Smaller in size than I though that it would be but, it definitely does its job as a motion activated sensor. It is super easy to install with included 3M tap to stick to the wall or if you prefer they have also included screws to secure it firmly. The DC cable that is included makes it easier to position it according to your preference so that it gets an optimal location wehere it covers most of the area. Operation is very simple with adjustable timer and sensiitivity levels for day and night and lasting operation from 15 seconds up to 5 minutes.