Plug indoor chime eliminates need for batteries.| Simply plug into any standard powerpoint.| May be moved around the home to other power points.| Long range radio-wave transmission up to 70 metres which allow you to place the door chime anywhere in your home, garden or garage.| Good neighbours feature: easy adjustment of channel selections will stop interference from neighbours who have a similar Door Chime.| Choose between two possible chime tones: Ding Dong and Westminster.| Name tag insert on Bell Press enables visitors to check they are calling at the right place.| 3 year warranty.