Two-Way Converter UART TTL to RS485 Operating voltage: compatible with 3.3V and 5.0V Support baud rate: 110-256000bps Operating temperature: -40 Celsius to +85 Celsius Communication signal: compatible with 3.3V and 5.0V Transmission distance up to kilometers (with 850 meters of 2 * 1.5 cable to do the test, it is recommended to use in the 800 meters, more than 800 meters, please add repeaters) Semi-hole process design, the thickness of 0.8mm, makes it easy to use as a combo board, it can also be welded terminal use Has RXD, TXD signal lights to observe send and receive status