Humminbird 727 5-Inch Waterproof Fish Finder and Dual-Beam Transducer Maximum resolution and power with pro-grade performance, expandable and upgradeable fishing system 5-inch, high-definition display with 640 x 320 pixels of resolution and 16-level grayscale 60-degree, and 20-degree beam for both fish location better bottom definition Water temperature and speed capable included, and GPS ready Measures 6.9 x 7.7 x 4.5 inches (W x H x D), and reliable to 1500 feet of depth