StarTech.com 4 Port PCI Express RS232 Serial Adapter Card - Single-Lane PCI Express - Breakout Cable - RS232 Extension - PCIe Serial Card (PEX4S553B) - serial adapter - PCIe - RS-232 x 4

The PEX4S553B 4-Port PCI Express Serial Card (with breakout cable) lets you add 4 RS232 serial ports using a single PCIe expansion slot. The PCIe Serial Card includes a 1-to-4 break out cable, which enables you to add 4 serial ports to a single low profile slot.