Lowrance 000-12636-001 Hook-3X DSI Sonar, W/455/800 XDCR Led-backlit color display with detailed 320 x 240 resolution that's easy to see in full sunlight & from wide viewing angles Downscan imaging view with dual-frequency 455 or 800kHz operation reveals easy-to-understand, underwater detail of fish-holding structure Patented downscan imaging transducer design can track bottom up to 55Mph Pages button allows user to quickly switch between 455kHz & 800 kHz sonar frequency options Dedicated quick keys allow user to zoom up to 4x the Standard view & focus on key fishing areas