Long-distance wireless transmission up to 500 meters in open areas with an air baud rate of 10kbps. Operating frequency range of 433-458.5MHz with up to 255 communication channels. Maximum 100mW (20dBm) transmit power with 10 adjustable levels. Built-in MCU uses serial port communication with external devices, sending 31 bytes at a time. Supports one-to-one and one-to-many transparent transmission communication through ID setting. Changing the serial port baud rate synchronously changes the air data rate (10kbps-100kbps). Features a three-minute initialization period for normal data transmission and AT command configuration using 'AT+ENABLE=1'. After three minutes, the module operates solely in data transmission mode. Product Name: VHF/UHF Radio Modem RS485 Wireless Transceiver 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 Mode Baud Rate: 1200, 2400, 4800, 9600 (Default), 19200 Open Ground Transmission Distance: 500M Size (Without Antenna): 74 x 24 x 16mm Recommended to purchase multiple units for network configurations. With 2 units, modules send data to each other. With 3 or more units, one operates as master device while others function as slave devices, working similarly to wired RS485 bus systems. Master device transmits data to all slaves. Any slave can transmit data received by master and other slaves. Only one device may transmit data at any time. Applications: IP PTZ Cameras, Modbus Temperature Sensors, LED Controllers, RS485 Relays, Remote Control Systems, Remote Measurement Systems, Wireless Meters, Smart Home Automation, Access Control Systems, Smart Meters. Color: Blue Material: Plastic and Metal Package Contents: 2 x 433M-458M VHF/UHF Radio Modem RS485 Transceivers (With Shell) Other products not included.