1. Long-distance wireless transmission (up to 500m in open area, 10kbps data rate). 2. Operating frequency range: 433 - 458.5MHz, with up to 255 communication channels. Maximum transmit power: 100mW (20dBm), adjustable in 10 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 through ID settings. Changing the serial port baud rate automatically adjusts the over-the-air data rate (10kbps to 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 setup. After this period, the module operates only in data transmission mode and does not accept AT 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: -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 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. Application: IP PTZ Camera Modbus temperature sensor LED Controller RS485 Relay Remote control and remote measurement systems Wireless metering Home automation Access control Smart meter Note: Lighting and display differences may cause slight color variations between the image and actual item. Measurement tolerance: +/- 1-3cm.