1. Long-distance wireless transmission (up to 500m in open area, 10kbps air data rate). 2. Operating frequency range: 433 - 458.5MHz, up to 255 communication channels. Maximum transmit power: 100mW (20dBm) with 10 adjustable power levels. 3. Built-in MCU; communicates with external devices via serial port. Sends up to 31 bytes per transmission. 4. Supports one-to-one and one-to-many transparent transmission via ID settings. Changing the serial port baud rate automatically adjusts the air data rate (10kbps to 100kbps). 5. Features a three-minute configuration window after power-on during which the module can be set to AT mode by sending 'AT+ENABLE=1' for parameter configuration. After this period, the module operates only in data transmission mode and AT commands are treated as regular data. 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 Transmit Power: -40 to +20dBm Receiver Sensitivity: -114dBm Operating Temperature: -25°C to +75°C Transparent Transmission Baud Rates: 1200, 2400, 4800, 9600 (default), 19200 Open Ground Transmission Distance: Up to 500m Dimensions (without antenna): 74 x 24 x 16mm Recommended for use with two or more units: - With 2 units: Module 1 and Module 2 can send data to each other. - With 3 or more units: One master device and multiple slave devices. Operates similarly to a wired RS485 bus. The master sends data to all slaves; any slave can send data to the master and other slaves. Only one device may transmit at a time. Applications: - IP PTZ Camera - Modbus temperature sensor - LED Controller - RS485 Relay modules - Remote control and remote measurement systems - Wireless meter reading - Home automation - Access control - Smart metering Color: Blue Material: Plastic + Metal Package Contents: 2 x 433M-458M VHF/UHF Radio Modem RS485 Transceiver (With Shell) Note: Other accessories shown are not included. Note: Lighting and display differences may cause slight variations in color representation. Measurement error allowed within +/- 1-3cm.