Raymarine B744VL Long Stem Bronze Thru hull Tri-ducer with Fairing Block

Discover Superior Marine Sensing with the Raymarine B744VL Tri-Ducer

Navigating challenging waters demands precision, and the Raymarine B744VL stands out as a robust solution for boaters facing hulls with steep deadrise angles or thicker cored constructions. This long-stem bronze thru-hull multisensor combines depth tracking, speed measurement, and water temperature readings into a single, streamlined unit. Operating seamlessly at dual frequencies of 50 kHz and 200 kHz, it delivers reliable data to enhance your fishing trips, navigation, or everyday cruising—without the clutter of multiple installations.

What sets this tri-ducer apart is its thoughtful engineering for real-world marine conditions. The extended stem ensures optimal positioning even on hulls that traditional sensors struggle with, while the included high-performance fairing block minimizes drag for smoother, faster passages. Boaters often praise its clarity in varied depths, from shallow bays to offshore drops, making it a go-to for serious anglers and sailors alike.

Key Performance Highlights

• Dual-Frequency Power: 50 kHz for deep-water probing up to 1,200 feet and 200 kHz for detailed high-resolution scans to 700 feet—perfect for targeting structure or bait schools.
• Compact Thru-Hull Design: Requires just a 2-inch hole, simplifying retrofits on wood or fiberglass hulls.
• Integrated Speed and Temp: Paddlewheel sensor provides accurate boat speed through water and real-time temperature, crucial for trolling or weather-aware planning.
• 600-Watt Capability: Matches the output needs of popular sounder modules, ensuring strong signal returns without overload.
• Beam Coverage: Expansive 45-degree beam at low frequency for wide-area searches and focused 12-degree at high frequency for precision.

With a 30-foot cable length offering flexibility in routing, this sensor integrates smoothly into your existing setup, supporting deadrise angles from 0 to 24 degrees for versatile vessel compatibility.

Engineered for Durability and Ease

The B744VL's bronze housing withstands corrosive saltwater environments, backed by Raymarine's commitment to quality. Its patented self-sealing valve is a game-changer: simply remove the insert for cleaning marine growth or winter storage, and it snaps shut to block water intrusion—no dry-docking required.

Fully recessing into the custom fairing block reduces turbulence, allowing hull speeds over 30 knots without performance loss. This setup not only boosts hydrodynamics but also protects the sensor from impacts, extending its service life on rough seas.

Streamlined Installation Guide

Installing the B744VL is straightforward for DIY enthusiasts or pros. Start by selecting a flat hull section aft of any strakes or steps, ensuring at least 12 inches clearance from the waterline. Drill the 2-inch hole, bed the thru-hull in sealant, and secure the fairing block at a 12- to 18-degree angle matching your hull's deadrise.

• Pro Tip: For steep deadrise hulls, the long stem keeps the face perpendicular to the waterline, maximizing bottom coverage.
• Route the cable away from electrical noise sources like engines or radios.
• Test in calm water post-install to calibrate speed and depth readings.

Compatibility shines with dedicated sounder modules, and for select multifunction displays, a simple adapter cable bridges the connection seamlessly.

Maintenance for Peak Performance

Keep your B744VL performing like new with routine care. Flush the paddlewheel monthly with fresh water to prevent fouling, and inspect the valve seal annually. In growth-prone areas, apply a marine antifouling paint to the sensor face. This low-maintenance design means more time on the water and less worry about downtime.

Users report exceptional longevity, often outperforming competitors in sandy or silty conditions where debris clogs lesser units.

Frequently Asked Questions