RAM 2.25" Ball Mount with 3.68" Round Base & 2" x 5" Rectangular Place for the Humminbird Helix 9, 10 & 12. Humminbird Helix 9. Humminbird Helix 10. Humminbird Helix 12. The round plate contains two mounting holes at 180-degrees and three mounting holes at 120-degrees.
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