Garmin GPSmap 478 GPS Receiver Product Features WAAS-Enabled, 12 Parallel-Channel GPS Receiver For Offshore Applications Features Built-In Marine Detail Charts Of The United States Coastline, Including Alaska & Hawaii Utilize Elements Of New Bluechart G2 Technology Preloaded With City Navigator Nt Detailed Street Maps Of The United States, Canada & Puerto Rico Technical Details Brand Name: Garmin Model: 010-00543-00 Receiver Description: 12 channel Connectivity Technology: USB Display Size: 6.95 inches Native Resolution: 480 x 320 Battery Average Life: 15 Hours MP3 player: Y