Lowrance Hook-4 Sonar/GPS Mid/High/Downscan Navionics+ Fishfinder 4" full color screen Sonar / GPS mapping combo Mid / High / DownScan USCAN Nav+ Advanced Signal Processing (ASP) reduces the need to manually adjust settings to see fish, structure and bottom detail more clearly TrackBack to review recorded sonar history including structure, transitions or fish targets, then pinpoint locations with a waypoint