Item Type: Serial Port Module_x000D_ Material: Printed Circuit Board_x000D_ Working Voltage: DC 5V (USB power supply)_x000D_ Function: To achieve simultaneous communication with a single USB to expand 4 UART serial ports. _x000D_ Applicable Scenarios: For electronic equipment, automation equipment. 1FUNCTION: Expanding a single USB to 4 UART serial ports, this serial port module can achieve simultaneous communication. 24 WAY TTL PORT: All the 4 serial ports are using XH2.54 port, and the 4 way UART all have TX or RX indicator to show statue. 3EASY SWITCHING: VCC, TX and RX can switch among 5V, 3.3V, 2.5V and 1.8V, and the switching is very quick and easy as well. 4WIDE APPLICATION: Allows for flexible application on electronic equipments and automation equipments, powerful and useful. 5GOOD WORKMANSHIP: Adopting excellent workmanship, the serial port module is not prone to cold joints, simple to install.1 x Serial Port ModuleDo not use the product in an electrostatic environment, otherwise static electricity will damage the electronic components.