Based on GSM communication protocol, it supports 999 authorized users Authorized users can remotely control the devices, systems, and machines connected to the product through SMS commands or phone calls No need to connect to the Internet, no phone charges Freely set control numbers Widely used in access control systems, garage doors, parking systems, and devices that can be connected to relay control, and can send notifications of remote control results (such as the opening and closing status of the door) to users (via SMS) Rated voltage: 9V-36V DC 1A Operating temperature: -10~60 Storage temperature: -20~60 Relative humidity: 10-90%, no condensation Communication frequency: GSM: Quad-band850/900/1800/1900MHz Antenna: 50 SMA Support wired switch: Yes Colour:As Shown Material:plastics Plug Type: UK plug,it applies to Malaysia, the United Kingdom and so on. Voltage: AC100-240V Package Contents: 1 x Access Controller Kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.