Fitment Will compatible with side imaging products only, in conjunction with a dual beam transducer only. Supports MEGA Side Imaging. This 720101-1 9 M SIDB Y 9-Pin Dual Beam Splitter Cable Compatible with Humminbird HELIX 5, HELIX 7, HELIX 8, HELIX 9, HELIX 10, HELIX 12, HELIX 15, 300 Series, 500 Series, 700 Series, 800 Series, 900 Series, 1100 Series and models that utilize 455kHz/800kHz, MEGA Imaging and MEGA Imaging+ frequencies. Function Instead of using a transducer switch, this Y-cable will get you access to use two transducers on one unit. Specifically, it is to isolate the 2D sonar to one transducer, and gather down/side imaging from another. Performance Improvement .
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