Go from box to boat to dash with the versatile GPSMAP 378 Portable Navigator. This combination color chartplotter and land navigator comes preloaded with maps for lakes throughout the continental U.S., in addition to detailed street-level mapping. Optional weather and sonar capabilities combined with the ability to conveniently add plug-in data cards, let you easily add more maps and features, making this one incredible GPS navigator for land and freshwater. With the optional GXM 30 antenna, you also have the option of receiving XM Satellite Radio's 150 plus channels of commercial-free music, sports, news, talk and entertainment programming. Weather and audio options travel with your plotter, whether you're navigating on land or sea.