The product can obtain 4 serial communication ports through the PCI-E slot of the PC host. It adopts the industry's stable and durable AX99100 chip with strong compatibility. Its good electrical performance design and stable and fast communication capabilities make it a wise choice for users of automation engineering applications The serial port can realize power supply on pins 1 and 9 Support special baud rate options Independent power chip, 5v/12v power supply can be realized without external power supply Computer host suitable for PCI-E slot, can provide 4 standard DB9 pin RS232 serial ports, each port is fully serial modem controlled with a bidirectional speed of up to 25Mbps, supports remote wake-up and power management functions Chipset:AX99100 Port Number:4 Serial Port PCI for Express 1x Slot The product appearance and printed words may vary depending on the batch, but this does not affect use. Colour:Black Material:PCB Package Contents: 1 * PCIe Expansion Card Only 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.