CABLE USB 3.0 FOR EXTERNAL HDD commonly feature a USB Type-A connector on one end and a Micro-B USB connector on the other. The USB 3.0 interface provides data transfer rates up to 5 Gigabits per second. Connector Types: USB Type-A: The standard, rectangular connector found on most computers. Micro-B USB:A smaller, rectangular connector often used for external hard drives and other portable devices. Data Transfer Rate:  USB 3.0 cables offer a maximum theoretical transfer rate of 5 Gigabits per second (Gbps).