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. Transmits up to 31 bytes at a time. 4. Supports one-to-one and one-to-many transparent transmission via ID settings. Changing the serial port baud rate automatically adjusts the wireless data transmission rate (10kbps to 100kbps). 5. Features a three-minute configuration window: within three minutes of power-on, the module can enter AT command mode by sending 'AT+ENABLE=1' for parameter setup. After this period, AT mode is no longer accessible and all data is transmitted normally without reserved commands. 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: -25C to +75C Transparent Transmission Baud Rates: 1200, 2400, 4800, 9600 (default), 19200 Open Area Transmission Distance: Up to 500m Dimensions (without antenna): 74 x 24 x 16mm Recommended for use with two or more units: - For 2 units: Module 1 and Module 2 can send data to each other. - For 3 or more units: One unit acts as master, others as slaves. Operates similarly to wired RS485 bus. The master sends data and all slaves receive. Any slave can transmit, and the master and other slaves will receive. 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 are not included. Note: Lighting and display differences may cause slight color variations. Measurement error allowed: +/- 1-3cm.