Sienoc 3 Port USB 3.0 to Express Card 54mm Adapter Card NEC Chipset 5.0Gbps Express Card is an interface to allow peripheral devices to be connected to a computer, usually a laptop computer. This USB Express Card aims at providing high-performance and modular expansion to both desktop and laptop by a lower cost and compact design. And this serial port express card for notebook laptop is compliant with standard 54mm port. This laptop 3 port USB express card can support hot swap function! And this laptop 3 port USB 54mm express card can support USB3.0, USB 2.0 and USB 1.1.