CY USB 3.0 Male to Dual USB Female Extra Power Data Extension Cable for 2.5" Mobile Hard Disk Black Work for 2.5" Mobile Hard Disk . 20cm USB 3.0 Male to Dual USB Female Extra Power Data Y Extension Cable Two USB female connector,One is for USB 3.0 power and data, another one for USB 2.0 power only. The power side cable does not work with iOS phones (Apple), It works with Android phones. Does one USB port not supply enough power for your USB device? Our cable allows for power to be taken from 2 USB ports, like a PC and External hard drive. Allows you to link 1 USB device into 2 USB Ports on your PC for more power. There are times you may have an external device, such as a portable 2.5 hard drive, and a standard USB cable is not able to transfer enough power to operate the device.