Four computers share one modem or printer. This high speed sharing device is bus-powered and supports all RS232C signals up to 230400 baud. Features auto/manual mode input port selection and selectable time-out settings. Optional AC power adaptor. Requires straight thru DB25 cables. (Connectors: 4 RS232 (DCE) DB25 Female / 1 RS232 (DTE) DB25 Male)