Garmin GST-43 Speed/Temp Thru Hull Transducer

The Garmin GST-43 Speed/Temp Thru Hull Transducer is the go-to instrument for anglers and boaters who demand accurate, real-time water speed and temperature data. Whether you're chasing stripers in coastal estuaries, navigating offshore grounds, or simply optimizing fuel efficiency on a long run, this thru-hull transducer delivers the precision you need to make informed decisions on the water. Built for retrofit installation into existing Nexus 43mm thru-hull housings, the GST-43 eliminates the need for costly hull modifications while upgrading your Garmin chartplotter or marine electronics system.

This dual-function transducer reads water speed with the precision needed for accurate GPS cross-checks and calculates hull speed efficiently, while its integrated temperature sensor monitors thermal conditions critical for fish location and engine performance. The thru-hull design provides superior stability compared to transom-mount alternatives, eliminating speed signal loss at high angles and delivering consistent readings in rough seas. Its seamless compatibility with Nexus 43mm thru-hull housings means you can upgrade your existing installation without returning to the boatyard, saving both time and money.

Serious anglers, charter captains, and cruising boaters benefit most from the GST-43, particularly those already running Garmin Nexus systems or compatible plotters. The transducer integrates seamlessly with Garmin's marine network, feeding speed and temperature data directly to your chartplotter, autopilot, and engine instrumentation. Installation is straightforward for users with existing Nexus 43mm housings—simply remove the old cartridge and install the GST-43 into the housing already secured to your hull, then sync with your Garmin system via the Nexus backbone network.