The CannonLink allows you to control up to six Cannon Mag20DT or Cannon Mag 20 DT/HS downriggers from your Humminbird 700 Series, 900 Series or Matrix Series fish finder that's equipped with Humminbird's Fishing System. Using the controls on your Fishing System, you can deploy or retrieve down riggers, hold a specific distance off the bottom regardless of bottom contour, cycle downriggers between two depths and adjust the Positive Ion Control.