Sabrent 4 Port Portable USB 3.0 Hub for Ultra Book, MacBook Air, Windows 8 Tablet PC - Black (HB-RUC4) Supports USB 3.0 transfer rates up to 5Gbps. Backwards compatible with all USB 2.0/1.1 devices and hosts Expand by connecting up to 4 USB 3.0, 2.0, or 1.1 devices to any USB 3.0 or 2.0 capable computer Compatible with all Windows/Mac/Linux systems.