Northstar's legendary SoundTrac™ gives you the ability to scroll back to a target in the screen's history, mark it, and easily navigate to it. The Northstar 491 is feature rich: 50/200kHz. 600/1000 W. Bottom Lock. A Scope. White Line. Alarms for depth, fish, and temperature. northstar matched transducers. Each feature can be tuned to fit your needs. Or, simply leave the 491 in auto mode and start fishing.

• Enhanced Target and Bottom Discrimination
• SoundTrac™ Navigate Back to a Target in the Sonar History Screen
• 50/200 kHz @ 600/1000W
• A-Scope
• Bottom lock Combined With Multiple Levels of zoom Allows Closer Inspection of Targets Near the Sea Bed
• Graphic Gain Control makes understanding and using gain settings simple