Silverstone Expansion Card Model SST-ECU04 Type: PCI-E 2.0 x 2 (10Gbps) Internal USB Ports: 19pin connector for dual USB 3.1 ports Data Transfer Rate: USB 3.1 (10 Gbps), USB 3.0 (5 Gbps), USB 2.0 (480 Mbps), USB 1.1 (12 Mbps) Operating Systems Supported: Windows 7 (32bit/64bit), 8/8.1/10 (32bit/64bit), Ubuntu/Linux/Mac OS Specifications: Power requirement: 5V via SATA 15-pin power connector USB 3.1 controller: ASMedia ASM1142 Power Management Support: USB 3.1 and USB 2.0 link power management Current protection Support: over current detection and protection Dimensions: 0.81 x 3.94 x 4.72 Weight: 0.11 lb.