1、The switch has seven independent relay switches and you can activates NO.1 relay switch by dialing its cell phone number.GSM‑RELAY‑4G is a wireless 4G remote control switch connected to the 4G mobile phone network. You can send SMS text to GSM‑RELAY‑4G to turn the switch on or off. 2、The switch will refuse a call without answering and refuse to open the device to which it is connected, so there is no charge for calling the phone and the authorized phone number that is being called can be identified. 3、4G design, through 4G, 3G and GSM, Net can work anywhere in the world and it can carry out remote password operation and password change. 4、All relay outputs can work in switch mode or pulse timing mode, and it support free control mode or security authorization number control mode, you can easily programming in minutes by using mobile phone or PC software. 5、You can disable the SMS reply function to save money, and the switch supporte quipment operation history LOG check and custom commands.It has 2 mode output, relay output with call mode and relay output with SMS control. 6、7‑channel 50V 30A 50 Hz relay contact, supporting main power failure alarm via onboard battery.Digital programming can be done quickly and easily using SMS or the on‑board quick teach button. Condition: 100% Brand New Item Type: 7 Channel Relay Switch Controlling Material: ABS Plastic Color: As Pictures Shown European Frequency: LTE-FDD: B1/B3/B5/B7/B8/B20, LTE-TDD: B38/B40/B41 WCDMA: B1/B5/B8, GSM/EDGE: B3/B8 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 4G/3G/GSM 7-Way Remote Switch Controller 1 x USB Cable 1 x USB Programming 1 x Antenna 1 x Manual