Raymarine Long Stem BTH Tri With Fairing Block

The Raymarine Long Stem BTH Tri with Fairing Block is a professional-grade transducer assembly designed for anglers and boaters who demand reliable sonar performance in demanding saltwater and freshwater environments. This transducer is engineered for through-hull mounting on vessels where the transom or hull geometry requires extended stem length and low-profile fairing to minimize drag and turbulence. Whether you're running a center console, sport fisher, or cruising sailboat, this tri-frequency transducer delivers the accuracy needed for precise bottom mapping, structure location, and fish-finding at depths from shallow flats to offshore waters.

The long stem design accommodates thicker hull applications where standard transducers would sit too shallow, ensuring proper water contact and beam alignment for optimal sonar clarity. The integral fairing block streamlines water flow around the transducer head, reducing noise artifacts and cavitation bubbles that degrade signal quality at cruising speeds. BTH (Bronze Through-Hull) construction provides corrosion resistance and durability in saltwater conditions, while the tri-frequency capability—typically 50 kHz, 200 kHz, and 455 kHz—enables flexible frequency selection for different depths, bottom types, and target species. Weighing 10 lbs, this assembly integrates seamlessly with Raymarine sonar systems and legacy marine electronics platforms that support standard transducer connectors.

This transducer is ideal for boaters upgrading aging sonar systems or building custom installations on vessels with non-standard hull configurations. Installation requires careful through-hull mounting with proper sealant and backing plates to prevent leaks and vibration. Compatibility extends across most Raymarine chartplotters, fishfinders, and multifunction displays from the last two decades, making it a solid retrofit choice for existing systems. Verify your specific Raymarine unit's transducer input type before ordering to ensure plug-and-play operation.