Telephone dialer installation on the control unit. - GSM 850/900/1800/1900MHz telephone dialer - 1 alarm input - Phonebook with 6 telephone numbers (3 for the SMS phonebook and 3 for the voice phonebook). - Possibility of programming the device to send SMS notifications only, calls only, or both SMS and calls. - In the event of an alarm, the device will send an alarm SMS with customizable text. - Once the cause of the alarm has ceased, the GSM dialer will send a customizable notification SMS to notify you that the alarm has been resolved. - Power supply 5 to 15Vdc - Dimensions 66 x 62 x 22mm If you were to program the device to send calls, we would like to point out that these would be silent, as the device does not handle audio. By storing the device's SIM number on your mobile phone, you'll immediately know what the call is when it arrives, without having to answer it. Given its small size, the dialer can be easily installed anywhere, even in a car. The important thing to consider is that whatever sensor or device is used to activate the dialer's input, it must not provide a voltage, but rather a free-switch relay. If the sensor or device provides an output voltage, it can be used to power the relay coil, whose output contacts will be used to activate the dialer. If installed in a car, it can be connected to the output of the existing alarm control unit to receive an alarm notification on your phone when the car's system goes into alarm. Before installing the device in a vehicle, it's necessary to check whether the voltage produced by the alternator is somehow filtered and stabilized to a voltage below 15 volts. If this is not the case, it will be necessary to take action to avoid damaging the device. Since the alternator generates voltage peaks that are certainly higher than 15 volts, failure to observe this precaution puts the integrity of the device at risk, and this type of failure would not be covered by the warranty. The package contains: n. 1 Mini GSM Telephone Dialer n. 1 Mini-stylus antenna with SMA connector n. 1 Lithium battery n. 1 Manual in Italian. It is very easy to program by sending simple SMS messages. NB: The product installed on the car may differ from the product in the photo.