4 PORT EXPANSION: adds 4 extra USB ports to desktop or laptop system using a single USB connection SUPPORTS: USB 3.0 transfer rates up to 5Gbps (640MBps), 10x faster than USB 2.0; Backward compatible with USB 2.0 or USB 1.1. Supports most Window 10, 8, 7, Vist, XP, & Mac OS X; Desktop updates need to be installed to ensure compatibility AC POWER ADAPTER: provides external power source when needed (5V power adapter length up to 70in); Comes with Over-Current protection from unforeseen power surges ALUMINUM HOUSING: offers durability and excellent heat dissipation for long life and reliable performance; Woven braided cable