The PEX4S553S 4-Port PCI Express Serial Card lets you add four ESD-Protected RS232 ports, with 5V or 12V selectable power output through a PCI Express slot. Ideal for industrial environments, this 4-port serial card offers built-in 15KV ESD-protection which helps prevent damage to connected devices in the event of line surges & electro-static discharge. Plus, for devices that require additional power, the multi-port serial card also has a jumper-selectable 5V or 12V power output option (pin 9) using either the PCIe bus, or through an SP4 connection to your power supply. For added flexibility, the power output can be enabled or disabled on a per-port basis so you choose which ports supply power.