Features: Equipped with the VL805 controller chip, supporting usb3.0 5Gbps fast speed transfer with backward compatibility to USB 2.0/1.1; Four usb3.0 ports enable simultaneous connection of USB drives, external hard disks, cameras and other devices, delivering several times faster transfer speeds for large files and significantly reducing waiting times. Compatibles mainstream operating systems including Win7/8.1/10/11, offering plug-and-play functionality without requiring additional driver. The VL805 chip delivers robust stability and high peripherally recognition rates, enhancing everyday operations. Optimised for 2/4U chassis with double power supply support. Low-power design accommodates 3.3V/1.05V power sources, compatibles usb3.0 low-power for sustained energy efficiency. Specifications: Component: PCB Size: 5.8x6.8x12cm Input: PCIEX1 compatibles PCIEX4/PCIEX8/PCIEX16 Speed:5Gbps Number of interfaces: USB3.0x4 Supported chassis: Supported by both large and small chassis Practicality: Suitable for desktop computer users who need to add USB interfaces Package Includes: 1PC PCIE to USB3.0 four-port expansion card 1PC Installation bracket 4PCS 4mm screw 1PC Chinese-English bilingual user manual note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.