This PCI Express RS232 serial adapter card lets you add four RS232 (DB9) serial ports to your computer through a PCI Express (PCIe) slot. The 4 port PCIe serial card enables you to interact with serial devices, such as card readers, printers, PIN pads, and modems, at speeds of up to 921.6Kbps. Maximum Compatibility With broad OS support, including for Windows and Linux, this PCI E serial card is easy to integrate into mixed environments. The card comes pre-configured with low-profile brackets and includes optional full-profile brackets, so installation is easy regardless of the case form factor. This card is a direct replacement for PEX4S952LP. PEX4S03LP is backed by a StarTech.com lifetime warranty and free lifetime technical support.