1、FUNCTION: Expanding a single USB to 4 UART serial ports, this serial port module can achieve simultaneous communication. 2、4 WAY TTL PORT: All the 4 serial ports are using XH54 port, and the 4 way UART all have TX or RX indicator to show statue. 3、EASY SWITCHING: VCC, TX and RX can switch among 5V, 3V, 5V and 8V, and the switching is very quick and easy as well. 4、WIDE APPLICATION: Allows for flexible application on electronic equipments and automation equipments, powerful and useful. 5、GOOD WORKMANSHIP: Adopting excellent workmanship, the serial port module is not prone to cold joints, simple to install. 1 x Serial Port Module Item Type: Serial Port ModuleMaterial: Printed Circuit BoardWorking Voltage: DC 5V (USB power supply)Function: To achieve simultaneous communication with a single USB to expand 4 UART serial ports. Applicable Scenarios: For electronic equipment, automation equipment.  Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.