The Moxa 4-Port RS422/485 PCIe interface card provides reliable serial communication connections for industrial computer applications. This low-profile expansion card enables stable data transmission through four independent serial ports and supports both RS422 and RS485 standards for versatile integration with industrial equipment, automation systems, and legacy devices. The PCI Express interface ensures high-speed data transfer with minimal system resource usage, while the low-profile format offers compatibility with compact industrial computers and embedded systems. Each port features automatic flow control and supports baud rates of up to 921.6 kbps for efficient communication with various industrial devices such as PLCs, HMIs, sensors, and controllers. The card includes screw terminal connections for secure wiring in industrial environments, with built-in surge protection and 2.5 kV isolation per port to prevent electrical disturbances and ensure stable operation under demanding conditions. The robust metal bracket provides mechanical durability, and the card operates in a temperature range of 0 to 60 °C for reliable performance in industrial settings. This interface solution is designed for applications requiring multiple serial connections in space-constrained systems, offering dependable communication for data acquisition, device control, and system monitoring tasks in manufacturing, transportation, energy, and building automation sectors. The card supports standard operating systems and comes with comprehensive driver software for easy installation and configuration.