The ICE 688ci HD Combo features a High Definition 480H x 640V 5" 256 color display with backlight, DualBeam PLUS sonar with 4000 watts PTP power output, GPS Chartplotting. In addition, it includes a card slot for maps or saving waypoints, as well as three programmable preset buttons to save your favorite views. Maximize your angling experience with the Humminbird ICE 688ci HD Combo fishfinder GPS system.