The Surface Interface Unit (SIU) is supplied with a standard Scout system and is a rack-mountable unit that supplies power and communications to the system’s transceiver. It’s connected to the user’s own PC or laptop via a serial or USB link and requires a 110–240V ac power supply.

Alternatively with portable Scout systems, the features of an SIU are incorporated into a portable, fully self contained Surface Command Unit (SCU) with integrated PC, large touch screen display, sensor interface and battery pack. This enables Scout to be operated independently from almost any type of boat. For details see Surface Command Unit.