Humminbird 737 5-Inch Waterproof Fishfinder Robust fish finder with maximum sonar coverage, and maximum expansion capabilities High-contrast, 5-inch, 16-level grayscale FSTN LCD display with 640 x 320 lines of resolution Memory card expansion slot for Digital Screen Snap Shot or optional Navionics Gold and HotMaps cartography Widest QuadraBeam PLUS sonar with 20-, 60- and 90-degree beams is reliable to 1,500 feet Fully GPS ready, and backed by a manufacturer's limited 1-year warranty