Star Tech-com-PEX4S232485-PCI-Express-2x RS232-2x RS485-Combo-Card-Star Tech-com-PEX4S232485-P-The-PEX4S232485-4-Port-PCI-Express-PCIe-Serial-Combo-Card-from-Star Tech-com-lets-you-add-two-RS232-&-two-RS422-485-serial-ports-to-your-PC-through-a-PCI-Express-expansion-slot-P-P-This-PCI-express-serial-card-is-a-single-card-solution-which-is-compatible-with-nearly-any-serial-communication-protocol-supporting-RS-232-RS-422-RS-485-2-wire-or-RS-485-4-wire-operating-modes-P-P-The-4-port-ser