The EC1S1P55254 1S1P 54mm Parallel/Serial ExpressCard (16550 UART) adds 1 RS232 serial, and 1 IEEE 1284 Parallel port to your laptop, using an available 54mm ExpressCard slot. This high-performance Serial/Parallel adapter with included breakout cable uses the full 54mm form factor for a perfect fit and long life durability. Supporting RS232 speeds up to 128Kbps and parallel rates up to 1.5Mbps, the serial/parallel adapter features a native chipset that delivers reliability, performance, and lower CPU loads versus conventional bridge-chip cards. Designed for use with laptop computers equipped with 54mm ExpressCard slots, this 1S-1P card offers a broad operating system compatibility list that includes Windows, Mac OS X and Linux, for simple integration into almost any system. The adapter also functions as a single port Parallel adapter if used without the included breakout cable. Backed by a StarTech.com Lifetime warranty and free lifetime technical support.