Lowrance 000-11817-001 Elite-4 Fishfinder/Chartplotter with Navionics, 83/200KHz Chirp and 455/800KHz DownScan Transducer High-resolution 4.3-inch LED-backlit color display CHIRP Sonar plus DownScan Imaging DownScan Overlay technology Advanced Signal Processing 50/200 KHz CHIRP and 455/800KHz DownScan Imaging transom mount transducer