Welcome to the store! 1. Long-distance wireless transmission (up to 500 meters in open area, 10kbps baud rate in the air). 2. Operating frequency range (433 - 458.5MHz, up to 255 communication channels). Maximum 100mW (20dBm) transmission power (10 power levels can be set). 3. Built-in MCU, use serial port to communicate with external devices. Send 31 bytes at a time. 4. The module can support one-to-one, one-to-many transparent transmission communication through ID setting. Changing the baud rate of another serial port will synchronously change the speed at which data is sent over the air. (10kbps-100kbps) 5. Set the 'critical three minutes'. The module can send and receive data normally within three minutes after being powered on. You can send AT 'AT+ENABLE=1' to make the module enter AT mode for parameter setting. There is only this reserved word during these three minutes. After more than three minutes, you will not be able to enter AT mode, you can only send and receive data, 'AT+ENABLE=1' will also be sent out as data, there are no reserved words at this time. Product Name: VHF/UHF Radio Modem RS485 Wireless Transceiver 20DBM 433mhz Transmitter and Receiver Working Voltage: 4.5V-5.5V; Interface: RS485(5V GND A+ B-) Frequency: 433MHz Transmission Power: -40~+20dBm; Receiver Sensitivity: -114dBm; Operating Temperature: -25 Celsius~+75 Celsius; Transparent transmission mode baud rate: 1200 2400,4800,9600(Default),19200; Open field transmission distance: 500M Size (without antenna): 74 x 24 x 16mm Recommended for more than 2 pcs!!! How to use (more than =2pcs): 1/2PCS, Module 1 and Module 2 send data to each other. 2 more than =3PCS, One as the master unit, the other will be as the slave unit. They work like a wired RS485 bus. The master unit sends data, the slave units receive all data. Any slave unit sends data, the master unit and the other slave units can receive. At any time, only one unit (master or slave) is allowed to send data. Application: IP PTZ Camera Modbus Modbus Temperature Sensor LED Controller R4D3C32 N4D8B08 N4D8C12 RS485 Relay Remote Control, Remote Measurement System; Wireless Meter; Smart Home, Home Automation, Wiser Home; Access Control; Smart Meter Color: blue Material: Plastic + Metal Package Contents: 1 * 433M-458M VHF/UHF Radio Modem RS485 Transceiver (With Shell) Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture to be slightly different from the real thing. The allowed measurement error is +/- 1-3cm. Your satisfaction is our top priority. We will provide you with the best service. If you encounter any problems after receiving the product, such as damage, incorrect quantity, etc., please contact us immediately and we will provide you with the best solution!