ONCHOICE 8 Ports Hub USB 2.0 High Speed Adapter Extension Cable ( not included power plug ) Attention Please: To ensure a stable connection, Do not use this hub with high power consumption devices , This hub is not meant to serve as a stand-alone charger.The hub will sync but not charge tablets and other devices that require a higher power input. If you do really need to connect those devices ( e.g. Mouse/ Keyboard/ External HDD) to the hub and sync the data , please use the power plug (not included) for offering them enough power. Expand USB connectivity by adding up to eight USB 2.0, or 1.1 devices to any USB 2.0 capable computer. Fully plug and play, devices can be hot-plugged, supports USB over-current protection. Transfer rates are device and USB host controller dependent. Backwards compatible with all USB 2.0/1.1 devices and hosts. All 8 ports on one side to minimize cable clutter and maximize accessibility. Note:1. multi-port USB HUB can connect low-power data transmission products, if all 7 ports to connect 7 removable hard disk or similar high-power data transmission products at the same time to copy data, then it may appear transmission speed slow down and the current instability. 2.HUB USB is in order to data transmission, not for charging. Therefore, the product is used as a charging function, the speed will be very slow, or will not work.