GARMIN 010-00459-00 Fishfinder 90 GPS Marine. The Fishfinder 90 wraps simple operations and Garmin s exclusive fishfinder technology into an entry level sonar. It is perfect for any vessel where space is at a premium. Dual beam transducer operation gives you better shallow water performance. The wide viewing angle /60 degrees/ lets you see fish even off the sides of the boat. With a basic black on white display, the Fishfinder 90 has one of the sharpest screens for the money. The Fishfinder 90 also offers Ultrascroll which allows boaters to get a much faster refresh rate on their sonar display. AutoGain, as well as user adjustable gain, is also standard on all of Garmins new fishfinders.