1. Two-way Communication: RS422 interface, two-way communication. Y Z ultra long distance transmission 1000 meters.2. Enhanced Protection: With built-in 15KV ESD protection and a 10-ohm current-limiting resistor, this module offers protection against electrostatic discharge and overcurrent situations. It ensures the safety and of your devices.3. Diode: Equipped with a diode, this module provides excellent resistance to thunder strikes and voltage spikes. The inclusion of a 120-ohm termination resistor effectively reduces long-distance communication reflect interference.4. Convenient Indicator Light: The module features power indicator and data transmission indicator, allowing for easy visual monitoring of the module's status. Additionally, module TTL side uses 5v DC power supply RXD TXD compatible with 5V logic signal.5. MAX490 Chip: This module incorporates an MAX490 chip, renowned for its stability and high communication speed. With a maximum transmission rate of 2.5MBPS, ensuring fast and reliable data transfer.Color:As ShownMaterial:PCBPackage Contents:2 * MAX490 To TTL ModuleOnly the above package content, other products are not included.Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.