APP remote monitoring; wireless calling system can send real-time updates to your mobile APP; so you can stay informed of family member's condition and respond quickly to provide the best care ^^ 2 power supply; type-c charging port and built-in battery; no need to worry if there is no power supply ^^ Expandable; the call button is expandable; up to 24 buttons; you can add more call buttons to meet the needs of various different usage scenarios ^^ 5 levels volume; caregiver pager has different levels of volume for you to choose; include mute; try our best to meet your needs ^^ Low battery reminder; when the host battery is less than 20%; the APP will push a low battery prompt message; no need to worry about low battery