Add two USB 3.0 ports to your laptop through an ExpressCard slot. The ECUSB3S2 ExpressCard USB 3.0 Adapter lets you add two USB 3.0 ports to your laptop through a 34mm ExpressCard slot. Enhanced with UASP support (USB Attached SCSI Protocol), this USB 3.0 controller performs up to 70% faster than conventional USB 3.0 when paired with a UASP supported enclosure (Note: UASP requires a compatible operating system). Using a more efficient protocol than the traditional USB BOT (Bulk-Only Transport), UASP technology optimizes transfers by allowing multiple commands to be processed simultaneously, significantly increasing transfer speeds for less wait time on data transfers. See our UASP test results below for further details. Featuring a native NEC host controller chipset, the USB 3.0 ExpressCard adapter is compliant with USB 3.0 standards for data transfer speeds up to 5 Gbps, while still offering backward compatibility with existing USB 2.0 / 1.1 devices. Backed by a StarTech.com lifetime warranty and free lifetime technical support. Improved Performance with UASP UASP is supported in Windows® 8, Server 2012 and Linux kernel 2.6.3 or later. In testing UASP performed with up to a 70% faster read / 40% faster write speed over traditional USB 3.0 at peak performance. At the same peak in testing, UASP also showed up to an 80% reduction in required processor resources. Test results were obtained using an Intel® Ivy Bridge system, StarTech.com add-on USB 3.0 cards, a UASP-enabled StarTech.com enclosure, and a SATA III solid state drive.