FF525 "Black Box Fish Finder Module" Features A-Scope; displays Sonar Echo in real time Preset modes;Fish & Cruise 2x and 4x Zoom;capability to magnify any part of the Fish Finder image of a fixed rate Bottom Lock;capability to magnify a user defined range around the bottom White Line;help distinguish between fish and bottom, when fish are swimming close to the bottom Surface Noise Filter;suppresses the displaying of Surface Clutter Dual Power output: 600/1000W (4800/8000Wpp) depending on the transduce..