Garmin GPSMAP 378 3.7-Inch Waterproof  Marine GPS and Chartplotter WAAS-Enabled, 12 Parallel-Channel GPS Receiver For Inland Boaters & Anglers Boasts 10 M Shoreline Resolution For More Than 3200 Lakes Across The Entire Continental United States Utilize Elements Of New Bluechart G2 Technology Preloaded With City Navigator Nt Detailed Street Maps Of The Us, Canada & Puerto Rico