See the link below:
Although I haven't used this particular combo, primarily, they're wireless devices.. The keyboard and mouse connect wirelessly to the receiver which usually is plugged into the computer USB port. . Both the keyboard and the mouse require batteries to enable their wireless systems to work and connect to the receiver. Sometimes, the USB extension cord is plugged from the computer into the receiver to allow it to be moved to a slightly different location on the computer, say on top, or put on a shelf nearby..
Once setup, you can sit across the room with the keyboard and mouse and they will make contact to the receiver and thus, to the computer.
Hope this helps.
there is a mini receiver with usb cable ATTACHED..the instructions
say put the usb cable into the receiver??? But, if you do that, what goes into the computer? there is no other usb cable or device..I am totally lost on this..if I plug the usb into the tower, why is there the usb slot on the little receiver...???? HELP