Garmin Course Computer Unit - Reactor™ 40

The Garmin Course Computer Unit - Reactor™ 40 is the autopilot brain your boat needs for precise, hands-free navigation in coastal and offshore waters. Built for anglers and boaters who demand reliability when conditions tighten, this marine-grade course computer automates steering control so you can focus on finding fish, monitoring sonar, or managing your crew. Whether you're running a tidal inlet, holding a waypoint in a crosscurrent, or maintaining a course line during a long offshore run, the Reactor™ 40 delivers the predictable, responsive control that separates confident boating from white-knuckle piloting.

This compact course computer integrates seamlessly with compatible Garmin chartplotters and autopilot systems to provide closed-loop steering feedback and dynamic course correction. The Reactor™ 40 processes heading, GPS, and tide data in real time, adjusting helm commands to compensate for wind, current, and sea state without constant manual correction. Its lightweight design—just 0.7 pounds—mounts cleanly in tight helm spaces, and the straightforward 6 x 3 x 8-inch footprint fits both classic wheelhouse layouts and modern console installations. The unit communicates via industry-standard marine networking protocols, ensuring compatibility with your existing electronics ecosystem.

Serious anglers, charter captains, and cruising boaters benefit most from the Reactor™ 40 when running trophy grounds where fuel economy and precision matter. Paired with a compatible Garmin autopilot drive and control head, it transforms your helm into a tireless first mate, holding tight lines in variable conditions while you work the rod or monitor weather. Installation requires integration with your vessel's steering system and a compatible Garmin autopilot package; consult your boat's electrical schematic and Garmin's integration guide to confirm compatibility with your specific chartplotter model and drive unit before purchase.