The IOGear Four-Port USB 2.0 Automatic Printer Switch allows for up to four PCs or Mac systems to share one printer. All the user has to do is submit a print job and the printer will automatically switch over to the preferred computer. The USB printer switch designed by IOGear can quickly and easily print images and documents from a connected computer in your home or office without the need of any external power supply source. This device not only allows multiple PCs to share a printer, but it also allows multiple users on a single external hard drive, scanner or other type of USB device. The IOGear printer switch can provide support for USB 2.0 devices and is USB 1.1-compatible. It allows you to get your printing job done faster, no matter how large or small it may be, with a data transfer rate of 480Mbps. With the IOGear automatic printer switch, you do not have to worry about extraneous wires because there is no need for an external power supply. printer.