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 interface. Supports sending up to 31 bytes per transmission. 4. Supports one-to-one and one-to-many transparent data transmission through ID configuration. Changing the serial port baud rate automatically adjusts the over-the-air data rate (10kbps–100kbps). 5. Features a three-minute configuration window after power-on during which the module can enter AT command mode by sending 'AT+ENABLE=1' for parameter settings. After this period, the module operates only in data transmission mode and all 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: -40dBm to +20dBm Receiver Sensitivity: -114dBm Operating Temperature: -25°C to +75°C Transparent Transmission Baud Rates: 1200, 2400, 4800, 9600 (default), 19200 bps Open Area Transmission Distance: Up to 500 meters Dimensions (without antenna): 74 x 24 x 16mm Recommended for use with two or more units: - For 2 units: Module 1 and Module 2 communicate bidirectionally. - For 3 or more units: One master unit and multiple slave units. Operates similarly to wired RS485 bus. The master transmits and all slaves receive. Any slave can transmit, and the master and other slaves will receive. Only one device may transmit at a time to avoid collisions. Applications: IP PTZ Camera Modbus temperature sensor LED Controller RS485 Relay modules Remote control and remote monitoring systems Wireless meter reading Home automation systems Access control systems Smart metering Color: Blue Material: Plastic + Metal Package Contents: 2 x 433M-458M VHF/UHF Radio Modem RS485 Transceiver (with enclosure) Note: Other accessories are not included. Note: Lighting and display differences may cause slight color variations. Measurement tolerance: ±1–3cm.