This is a multi-function dual micro USB host OTG hub adapter cable.two ports with USB design，can connect the keyboard，mouse，card reader，and so on. Two ports with USB design，can connect the keyboard，mouse，card reader，and so on(can't connect hard disk). One power USB port can connect original charger supply power for flash disk， card reader ，mouse，keyboard，so on. Note: The hard disk must have external power， and the disk format must be FAT32， It cannot read NTFS. The Micro-USB port can connect the original charger to provide power for the USB flash disk， card reader， Keyboard，mouse， or USB hard disk that is connected to the other USB ports on this On-the Go (OTG) cable. But PLEASE NOTE that the Micro-USB power from your charger CANNOT CHARGE YOUR TABLET OR PHONE!!! It will only provide power to the On-the-Go (OTG) Ports. Compatible with: for Dell Venue 8 / Venue 8 Pro Android Operating system Tablet Series. for Dell Venue 8 Pro Windows Operating system 8" Tablet Series Package including: 1x Micro USB Host OTG Hub Adapter Cable