Add a parallel port and two RS-232 serial ports to your PC through a PCI-Express expansion slotThe PEX2S1P553B 2S1P PCI Express Serial Parallel Combo Card with Breakout Cable combines the functionality of Parallel and Serial cards. adding 2 RS232 serial ports and 1 parallel port through a single PCI Express (PCIe) slot.Suitable for almost any computer. the card offers a low profile/half-height design and includes an optional full-height bracket. The included break-out cable uses a single connector on the card to deliver 3 ports. avoiding crowded connections that can occur with fixed/static ports. Compatible with a broad range of operating systems including DOS. Windows 7/Server 2008 R2/Vista/XP/Server 2003/2000/98SE (32/64 bit). Linux and Mac OS X.The card also features a native single-chip design that provides improved speed and reliability while reducing the CPU load by as much as 48% over conventional (bridge chip) cards.This product is a replacement for our PEX2S1P552B card.Backed by a StarTech.com Lifetime warranty and free lifetime technical support.The StarTech.com Advantage- Break-out cable design with low and standard profile brackets offers a versatile. single slot solution for adding 3 additional ports (2 serial. 1 parallel) to almost any system. including space-sensitive embedded applications- Native single-chip design reduces CPU load for improved performance and reliability- Broad Operating System support. including 64-bit Windows systems. for easy integration into mixed environments