Raymarine B75LM 12DEG Pair Thru Hull Chirp Transducers

Discover Superior Underwater Clarity with the B75LM 12° Pair

Upgrade your vessel's sonar capabilities with this precision-engineered thru-hull CHIRP transducer pair, designed for boaters who demand exceptional target definition across varied depths. Ideal for fiberglass or wooden hulls, these bronze units deliver reliable performance in marine environments, capturing everything from bait schools to bottom structure with unmatched resolution.

What sets this setup apart is its dual Low and Medium frequency bands, allowing seamless switching between wide-area scanning at shallower depths and pinpoint accuracy in deeper waters. Anglers and navigators alike benefit from the variable beamwidth—starting broader for quick coverage and narrowing for detailed imaging as frequencies rise—ensuring you never miss the action below.

Why Choose CHIRP Technology for Your Next Adventure

Traditional sonar often struggles with clutter and poor separation, but CHIRP sweeps across frequencies continuously, producing vivid, high-contrast images. With this pair mounted correctly, you'll enjoy enhanced vertical resolution, spotting fish close to the bottom or separated wrecks effortlessly. The 600W power handling supports integration with compatible sounders, pushing signal strength for reliable returns even in challenging conditions like thermoclines or heavy currents.

For offshore trips or inland lakes, the Low band (40-75 kHz) excels at penetrating to hundreds of feet, while the Medium band (80-130 kHz) sharpens inshore details. Paired units minimize dead zones on angled hulls, providing a fuller picture without the guesswork of single transducers.

Perfect Fit for Your Hull Design

The 12° tilt aligns the beams perpendicular to the waterline on hulls with moderate deadrise, optimizing energy projection downward. Bronze construction resists corrosion in saltwater, and the included Y-splitter simplifies cabling for dual-channel setups. Whether you're trailering a center console or cruising a cruiser, thru-hull mounting keeps transducers secure and streamlined, free from trolling motor interference.

Pro tip: Position the pair symmetrically fore or aft of the keel for balanced coverage, and fair them into the hull to reduce cavitation noise. This configuration shines on planing hulls, maintaining crystal-clear returns at speed.

Real-World Performance Insights

Boaters report game-changing improvements in marking structure—reefs, drop-offs, and ledges pop with lifelike detail. The temp sensor adds another layer, tracking water column changes that influence fish behavior. In competitive fishing circuits or casual outings, this transducer pair elevates situational awareness, helping you troll lures precisely or anchor over sweet spots.

Compared to plastic or embedded options, the robust build handles repeated launches without signal loss, and CHIRP adaptability outperforms fixed-frequency rivals in diverse fisheries from the Gulf Stream to Great Lakes shallows.

Installation Essentials for Peak Results

Prep your thru-hull hole with a clean cut, apply marine sealant generously, and torque to spec for a watertight seal. Route cables away from engines to dodge EMI, and test across frequencies post-install. For multi-display networks, the CP450C connectors play nice with standard Raymarine ecosystems, unlocking advanced features like side-scan fusion.

• Verify hull thickness compatibility (up to 2 inches recommended)
• Pair with high-output amplifiers for max depth potential
• Calibrate beam angles in software for your specific setup