Humminbird 365i 4-Inch Waterproof Marine GPS and Chartplotter Compact chartplotter/fishfinder with 4-inch grayscale display, DualBeam sonar with 2400 Watts PTP power output. with 4 Inch LCD display Dual-beam Switchfire Sonar with precision 20-degree beam and wider 60-degree beam; view beams separately, side-by-side, or blended together Real-time Sonar always updates at the fastest rate possible, shows returns from the bottom structure. Included UniMap covers the continental U.S. coastline, inland lakes, and rivers at 30 meters per pixel resolution Built-in card slot allows you to upgrade to a Navionics chip for enhanced navigation and map detail GPS Chartplotting with built-in UniMap