1、The GSM‑AUTO 4G version is a wireless remote switch that can be controlled by a 4G mobile phone.By purchasing a SIM card and a pay‑as‑you‑use (PAYG) plan from a local wireless provider, you can connect to a 4G or 3G or GSM cellular network. After installing the SIM card into the SIM card holder on the top of the GSM‑AUTO 4G module, it will have its own unique phone number, which can be activated by typing in its mobile phone number. Or, you can send SMS text messages to the device’s phone Number to activate each relay. 2、The unit cannot answer voice calls, but when a call is sensed, its logic will activate one or two output relays in a pre‑programmed sequence. Since the device does not answer the call, the activation of the relay will not affect the PAYG plan or the caller. For any call charges, it will recognize the authorized phone number and reject the call and answering. 3、4G design, can work anywhere in the world through 4G, 3G and GSM Net, GSM‑AUTO unit controls 2 independent switches. Therefore, you can control 2 separate devices from one device. An example is in an aircraft hangar, turning on the battery charger and engine preheater in sequence to prepare the aircraft for flight. 4、The secure caller ID allows to control the access of up to 100 authorized users. The user's phone number is added to the whitelist. Only the numbers in the whitelist can activate GSM‑AUTO. You can use text to add and delete user messages as needed. 5、GSM‑AUTO has two independent relays. They have normally open and normally closed contacts. They can be programmed to open between 1 second and 18 hours. In addition, the delay time between relay 1 and 2 switching can be set by sending a text message to GSM‑AUTO, once programmed, you only need to call the unit to activate the programmed relay operation. Similarly, program the unit by sending a specific SMS text command. 6、By sending a text message command to the device, you can temporarily cancel the programmed operation and open the relay for up to 18 hours. When the relay is open, a confirmation text will be returned, and when the relay is closed, another confirmation text will be returned. You can also send GSM‑AUTO to permanently open or close the relay, send a short message, and return to confirm the short message again. 7、The onboard clock and 24‑hour timer (each relay has 8 time periods) enable the relay to be turned on and off within the set time, for example, set relay 1 to 0600 (6 am) and 1900 (7 pm) ) Will open. The timer function repeats once a day until reset. When the 24‑hour timer is enabled, the caller ID and priority functions will be disabled, and the onboard battery can be used for power failure alarm (battery not included). 8、Applications include remote control of heating of holiday houses, lighting, engine preheaters, aircraft engine heaters, irrigation systems, water well pumps, pumping stations, cabin heaters, resetting of remote servers, arming and disarming security systems, and doors Access control and garage door. Condition: 100% Brand New Item Type: Remote Control Box Material: ABS Plastic Color: As Pictures Shown Working Voltage: AC100-240V Working Current: Maximum 450mA, Typical 60mA Relay Contact: Dual Relay Output Channels: Normally Open and Normally Closed Alarm Input: One Alarm Output Working Temperature: -20 to 55°C Protection: IP65 European Frequency: LTE-FDD: B1/B3/B5/B7/B8/B20, LTE-TDD: B38/B40/B41 WCDMA: B1/B5/B8, GSM/EDGE: B3/B8 US Frequency: LTE-FDD: B2/B4/B12, WCDMA: B2/B4/B5 Australian Frequency: LTE-FDD: B1/B3/B7/B8/B20/B28A, LTE-TDD: B38/B40/B41 WCDMA: B1/B8, GSM/EDGE: B3/B8 1 x Wireless Remote Switch Controller 1 x Long Antenna 1 x Short Antenna 1 x USB Cable 1 x USB Programming 1 x Manual