Features 1、1-Channel GSM SMS alarm, external rechargeable battery (not included) for power failure alarm. 2、Send SMS alert messages to up to 6 preset mobile phones when any alert input is triggered. 3、The input of GA01P is the switch signal. When the input port is shorted to the ground (GND), GA01P will send an alarm message to the preset mobile phone, or call the set alarm number. 4、The content of the alarm message can be set by itself. You can use text custom alert SMS. 5、Smart and slim gsm design box for easy installation on other target system boards, adding gsm alarms. 6、Can be widely used to connect different sensors. Such as door magnetic switch, infrared sensor, GAS detector, water level sensor, temperature measuring device. Specification Item Type: GSM Power Failure Alarm Material: ABS Plastic Power Input: DC6-15V Package List 1 x GSM Power Failure Alarm 1 x Antenna 1 x Audible Alarm