A80010 B265LH D/T Bronze CHIRP Transducer for CP470 (Low/High)

Raymarine B265LH (Part # A80010) is a top-of-the-line thru-hull CHIRP transducer designed for serious offshore fishing and high-detail sonar applications. Featuring dual CHIRP frequency ranges (Low and High) and a potent 1 kW power rating, this bronze transducer delivers both extreme depth penetration and razor-sharp target resolution to meet the demands of professional anglers and navigators. The B265LH leverages CHIRP technology to sweep across two distinct frequency bands – a low band for deep waters and a high band for detailed imaging – essentially giving you two specialized transducers in one housing.

In Low CHIRP mode (42–65 kHz), the B265LH can reach depths of approximately 3,000 ft (around 900 m) under ideal conditions. This tremendous depth capability allows you to explore continental shelf drop-offs, deep canyons, and blue-water hunting grounds where big game fish roam. The low-frequency beam width (about 25° at 42 kHz, narrowing to ~16° by 65 kHz) is broad enough to cover a large swath of the water column and seabed, which is invaluable for surveying wide areas for structure and schools in deep water. Low CHIRP’s longer wavelengths also excel at maintaining bottom lock and penetrating through thermoclines and plankton layers, giving you consistent depth readings and clues to the seafloor composition even in very deep or murky conditions.

In High CHIRP mode (130–210 kHz), the transducer focuses on shallower depths (up to roughly 1,000 ft or 300 m) with exceptional clarity and detail. The high-frequency beam is very narrow – around 10° at 130 kHz tightening to an ultra-narrow ~6° at 210 kHz – meaning the transducer concentrates its energy in a small cone for maximum resolution. This narrow high-frequency beam enables the unit to separate individual fish targets and reveal fine structures on or near the bottom (for example, distinguishing fish close to the seabed or picking out small wrecks and reefs). For the angler, this translates to the ability to discern game fish from bait fish or clutter and to have a much clearer picture of what’s immediately below the boat when precision is needed (such as when dropping bait to specific targets or investigating a particular spot).

By utilizing both Low and High CHIRP bands, the B265LH offers unparalleled versatility: the low-frequency channel covers the deep water action, while the high-frequency channel provides micro-detail in the upper layers. When used with a compatible dual-channel sonar (like the Raymarine CP570), both CHIRP channels can operate simultaneously, giving you a split-screen view – one view showing deep bottom structure and fish, and the other zoomed in on the mid-to-shallow depths – with no compromise in performance. This dual view can greatly enhance situational awareness, ensuring you don’t miss anything in the water column.

To facilitate optimal performance, the B265LH includes a fairing block for proper installation on hulls with deadrise angles up to 20°. The fairing block ensures the transducer face is oriented vertically downward on V-hulled boats, which maximizes echo return strength and accuracy. By fairing the transducer, you also reduce aeration and turbulence in front of the sensor. The result is a stronger, cleaner signal and the ability to hold bottom at higher speeds. In practice, this means the B265LH can keep a reliable lock on the bottom even when the boat is on plane, allowing you to gather depth data and mark fish while cruising between spots – a key advantage for tournament sportfishers and fast-moving vessels.

As expected from a premium transducer, the B265LH outputs both depth and water temperature. The integrated temperature sensor is a valuable tool for finding thermal breaks and currents which often indicate favorable fishing zones. The unit’s construction is heavy-duty bronze, built to endure the rigors of saltwater usage for years on end. (It is intended for fiberglass and wooden hulls; if you have an aluminum or steel hull, you would need to use an appropriate fairing and isolation kit or a different transducer model to avoid galvanic issues and signal distortion.)

Compatibility: The Raymarine B265LH comes with an 11-pin cable/connector assembly that plugs directly into Raymarine’s CHIRP sonar modules – specifically the CP470 and CP570. It is also compatible with the older CP450C CHIRP module. For newer Raymarine multifunction displays that feature built-in CHIRP sonar (such as the Axiom Pro RVX or Axiom 2 Pro series), the B265LH can be connected using the same 11-pin interface, effectively upgrading your system with 1 kW CHIRP capabilities. A 33 ft (10 m) cable is attached to give ample length for running to your electronics, even on larger boats.

The Raymarine B265LH is recommended for larger sportfishing boats and commercial vessels (around 33 ft / 10 m or more) where ultimate sonar performance is desired. Its ability to delve into the depths and simultaneously provide crisp detail in shallower ranges makes it ideal for offshore captains who need to track deep-water targets like tuna or swordfish, yet also monitor what's happening closer to the surface or around structures. With the B265LH, you can confidently map out the entire water column beneath your boat and pick out targets that lesser transducers might miss. It comes with Raymarine’s 2-year warranty, reflecting its robust build and quality. To keep the transducer performing at its peak, remember to apply a transducer-safe anti-fouling coating to the bronze face and periodically clean off any marine growth.