StarTech.com 2 Port PCI Express (PCIe) SuperSpeed USB 3.0 Card Adapter with UASP - SATA Power - Dual Port USB 3 PCIe Controller (PEXUSB3S24) - USB adapter - PCIe - USB 3.0 x 2 - for P/N: CFASTRWU3, ST3300GU3B, ST4300U3C1, ST4300U3C1B, ST7300U3M, ST7300USB

The PEXUSB3S24 2-Port PCI Express USB 3.0 Card lets you add two USB 3.0 ports to your PCI Express-enabled computer system, with an optional SATA power connector to connect to your system power supply and deliver up to 900mA of power per port to USB 3.0 bus-powered devices (500mA for USB 2.0).
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 External Drive Enclosures. 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.
The PCIe USB 3.0 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. For added versatility, the controller card is equipped with a standard profile bracket and includes a low-profile/half-height bracket for installation in small form-factor computers.

• Provides two external USB 3.0 ports with UASP support
• Supports data rates up to 5 Gbps
• Compliant with PCI Express 2.0 specifications
• Supports USB Battery Charging Specification 1.2
• Fully compliant with USB 3.0 rev 1.0 and Intel xHCI rev 1.0 specifications
• Backward compatible with USB 2.0 and USB 1.0/1.1 devices
• Includes a low-profile/half-height installation bracket