Humminbird's DualBeam sonar combines the advantages of narrow- and wide-beam transducers into one system with wide coverage and better bottom definition. Its precision 20° at -10db 200kHz down-looking center beam looks for fish and structure directly below the boat, while the broad 60° at -10db 83kHz wide beam looks for fish outside the narrow beam around the boat. The Fish Identification feature gives more information on location than a traditional single beam: Fish in the narrow beam are displayed as solid fish symbols; fish in the wide beam are shown as hollow fish symbols. All-new housing design with SD card slot.