This video doorbell is one of the smallest sizes in the industry, and the designer has specially designed it according to the size of the American home door frame. has video intercom,taking photo, video, night vision,PIR and other functions to make your life more convenient.ideo doorbell is one of the smallest sizes in the industry, and the designer has specially designed it according to the size of the American home door frame. has video intercom,taking photo, video, night vision,PIR and other functions to make your life more convenient.