I was reorganizing my desks and found two different triple-ended USB cables. I don't know their origin or purpose. I have never seen triple-ended USB cables before. What are they used for?

enter image description here enter image description here

  • 6
    Known as Y-cables, usually to give a device more power when the normal 500 mA per USB port is not sufficient.
    – ott--
    Mar 1, 2013 at 22:38
  • Related: superuser.com/questions/448722/… Mar 23, 2013 at 15:14
  • They are used for starting fires and damaging expensive electronics. Stay very far away from these cables.
    – MacGuffin
    Jun 28, 2021 at 9:12

1 Answer 1


The lower cable is most likely for an external (2.5") hard drive. Often these used to require more than the USB-provided 2.5W, so two ports were used to get 5 Watts, even though this violates the USB standard in most cases, it still works.

About the triple USB A-plug cable on top - the only idea would be that a manufacturer would save money and equipped their device with a A- instead of a B-receptable which is normally used for devices. And it's crazy and dangerous.

  • 2
    Also the upper USB cable is for an external HDD. The connector with two cables attached must be plugged into the host computer. Then the connector with the short cable, too. (Here, only the power lines are wired). Last, the longest cable is for the external HDD.
    – mpy
    Mar 1, 2013 at 22:45

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .