The Lowrance PSI-1 Performance sonar interface is used in conjunction with the LiveSight sonar sensor installed on your HDS Carbon system (none of which is included), allowing you to observe the fish's response to the bait in real time. The Lowrance PSI-1 performance sonar interface provides you with unparalleled insight, including working principles, shortcomings and next steps. It is easy to install and has a small footprint. Colour: Black.