Thanks to the Asus USB A to micro USB Bdongle (adapter) you can connect your different devices to your ZenFone or tablet.
It will allow you, among other things, to connect your ZenFone to the USB port of your laptop.
If you have a ZenFone 4 you will also be able to charge another phone with this black cable, because the Zenfone 4 contains a 4100 mAh battery, it is a powerful enough battery to also charge another smartphone.
For gamers, the USB A to USB B dongle is also useful, as it allows them to connect their smartphone to a console controller and enjoy their Android games like on a home console. You can also connect all your devices with the same connection.
You will have understood that this cable is an essential to always have on hand, to connect your Zenfone and your tablet to all possible devices.