Best Quality Guranteed. Package includes: The panel size is 5.25 inches, which is used to expand the chassis of the optical drive. There are 6 ports in total, 2xUSB 3.0 ports, 2xUSB 2.0 ports, 1x HD audio output port, 1x microphone input port. Advantages: The conductor of the USB3.0 high-speed cable is made of tinned copper, and the 3-layer shield improves the stability of data transmission. The audio interface adopts the HD Audio scheme, which has a larger transmission bandwidth, higher playback accuracy and stronger anti-interference than the AC97 of the chassis. Operating system compatibility: Windows XP / Vista / Server / 7/8/10, Linux. Simple and convenient: No need to download any driver, no external power supply, the built-in connection cable, plug in the interface and use it. Durable: Reasonably designed interface, lightweight galvanized steel plate to prevent oxidation and corrosion, longer service life. It undergoes two electrical tests b