This Phone Notification package from Bellman & Symfon is part of the Visit Smart Home System that helps you to keep tabs on your home. This package includes a Telephone Transmitter, Mobile Phone Sensor, and Pager Receiver. Those alerting devices in this package are already paired as a system and ready to use out of the box. Just connect your landline phone to the Telephone Transmitter, place the Mobile Phone Sensor on the screen of your cell phone or tablet, and then attach the Mobile Phone Sensor to the Telephone Transmitter. When there are incoming calls, messages, or social media notifications from your landline phone, cell phone, or tablet, you will get alerted with colored LEDs and vibrations from the Pager Receiver. The Pager Receiver is powered by a single battery so you can easily carry it as you walk around in your home and still get the alerts. This package is a great signaling system to help people with hearing loss, hard of hearing, and deaf to stay in touch with family and friends.