Add a USB (Universal Serial Bus)-based RS232 Serial port to your laptop through an Express Card slot. The EC1S232U2 Express Card RS232 Serial Adapter Card (USB (Universal Serial Bus)-based) (16950 UART) adds an RS232 (DB9) serial port to your Express Card-equipped laptop, enabling you to connect an RS232 serial peripheral device such as a plotter, digital signage device, receipt printer or bar code scanner through an available Express Card slot.