Add 4 high-speed RS-232 serial ports to your computer with a buffered serial card from Star Tech.com. The card uses a 16-Byte buffer in both the receive & transmit channels simultaneously, reducing the number of CPU interrupts & improving system performance. Compatible with both 3.3 & 5 volt motherboards, & uses DB9 connectors for use with a wide range of serial peripherals. Suitable for industrial applications, this card is compatible with a wide range of operating systems, including Windows, DOS, Linux, & Unix.