The us221a is a 2 port usb 20 peripheral switch that allows up to 2 computers to share the use of a single usb peripheral device such as a printer scanner mass storage drive etc on a one at a time basis the peripheral focus can be given to a computer manually by using pushbuttons on the switch using the software based configuration utility or by the auto switch function with multifunction printer support the us221a is the ideal way to share the usb 20 peripherals in a multimedia of