Furuno B175M Bronze Thru-Hull CHIRP Transducer 1kW

The Furuno B175M is a bronze thru-hull transducer built for anglers and cruisers who want real depth capability and sharp sonar detail. It's a medium-band CHIRP transducer, sweeping a range of frequencies from 85 to 135 kHz rather than pinging a single tone. That sweep is what gives CHIRP its edge. It packs more information into every return, so you get better target separation, cleaner bottom tracking, and the ability to pick individual fish out of a tight school that older single-frequency sonar would smear into one blob.

With 1 kW of power handling and that medium frequency band, the B175M is tuned for reaching down deep while still resolving detail. It's rated to display bottom to roughly 1500 feet in good conditions, which makes it a strong match for offshore fishing, deep structure, and blue-water passages where you need to know what's beneath the keel. The beam narrows from about 16 degrees to 11 degrees across the CHIRP sweep, giving you a focused cone that holds detail as depth increases and cuts through the noise that wide, cheap beams throw up.

This is a thru-hull design, meaning the transducer mounts through a hole in the hull with the active face in direct contact with the water. That direct coupling is the gold standard for sonar performance, because there's no hull material between the element and the water to weaken the signal. The B175M uses a tilted element, so the sound beam fires straight down even though the housing sits at the natural deadrise angle of the hull. Choosing the version that matches your hull's deadrise keeps the beam vertical and your readings honest, which matters when you're trying to mark fish holding right on the bottom.

The body is cast bronze, the traditional and time-proven material for a below-waterline fitting. Bronze is strong, corrosion-resistant in saltwater, and gives you a solid, serviceable housing that stands up to years of immersion. Along with depth, the B175M reads water temperature, feeding your sounder the surface temp data that helps you find thermoclines, temperature breaks, and the conditions that concentrate bait and gamefish. It's a lot of capability packed into one fitting.

• Medium-band CHIRP performance from 85 to 135 kHz
• 1 kW power handling for deep, detailed returns
• Bronze thru-hull housing with a tilted active element
• Depth capability to roughly 1500 feet in good conditions
• Built-in water temperature sensor

The B175M terminates in a 10-pin Furuno connector and comes with roughly 33 feet of cable, so it's ready to plug into compatible Furuno CHIRP sounders and fishfinders that share that mix-and-match connector. Because it's a genuine Furuno transducer, you can trust it to work to specification with the matching sounders rather than gambling on an adapter and hoping the tuning lines up. That's the kind of confidence you want in a part that has to perform right the first time, offshore, with a hole cut in your boat.

Picture a morning offshore, working a deep ledge in 400 feet of water. With the B175M feeding your sounder, you can watch bait stack up along the structure, pick out the bigger marks holding just off the bottom, and see the thermocline where the water changes. That's the difference a proper 1 kW medium CHIRP thru-hull makes. You spend less time guessing and more time putting your baits where the fish actually are. Installation is a job to take seriously, since it involves cutting through the hull below the waterline, but the payoff is the best sonar picture the electronics can produce. Pick the deadrise version that matches your hull, bed it properly, and route the cable to your sounder. From that point on, the Furuno B175M quietly does the heavy lifting, turning raw echoes into the clear, trustworthy picture of the water column that helps you read structure, mark fish, and fish with confidence.