✔The adapter has four independent 18-pin standard serial ports, such as the integrated serial interface, which makes the connection more stable. | ✔The adapter is a PCI-E 4-port RS232 serial port card, it has four ports so you can connect more HDMI cables as possible. | ✔Data transfer rates of up to 250 Kbit / s on each port, compatible with 16C550 UART, 256 byte on-chip FIFO depth when sending. | ✔Good performance - the adapter is well made, providing stable and effective data loss control. And it supports hot swap. | ✔Perfect solution for connecting to POS systems, industrial test and control devices, security systems, logistics management systems, printers, scanners, etc.