Furuno B285M Medium-Frequency CHIRP Transducer w/Temperature - Bronze Thru-Hull w/High Speed Fairing Block

Upgrade your sonar game with the Furuno B285M, a powerhouse medium-frequency CHIRP transducer designed for boaters who demand crystal-clear underwater visuals at greater depths. Whether you're chasing trophy fish in deep offshore waters or navigating murky coastal zones, this bronze thru-hull mount delivers exceptional target separation and bottom detail that standard fixed-frequency units can't match. Paired with its included high-speed fairing block, it minimizes drag and maintains performance even at planing speeds, making it a favorite among serious anglers and commercial operators alike.

Revolutionize Your Fishfinding with Medium-Frequency CHIRP

At the heart of the B285M lies its versatile CHIRP technology spanning 85-135 kHz. Unlike traditional transducers that lock into a single frequency, CHIRP sweeps continuously across this range, emitting a precise blend of frequencies tailored to your environment. This results in sharper images of fish arches, bait balls, and wrecks—especially in the 300-1,000+ foot depths where medium frequencies shine. Imagine spotting a school of snapper huddled over structure with pinpoint accuracy, giving you the edge to drop your lines right where they bite.

Users rave about how this transducer cuts through thermoclines and suspended particulates better than high-frequency options, which often lose steam below 200 feet. It's not just about seeing deeper; it's about seeing smarter, with enhanced vertical resolution that reveals fish size and behavior for smarter decisions on the water.

Integrated Temperature Sensing for Smarter Fishing

Water temperature fluctuations dictate fish movement, and the B285M's built-in thermistor captures real-time data with impressive accuracy. Track surface temps to locate upwellings or monitor changes as you troll, helping you zero in on species like tuna that follow thermal breaks. This dual-purpose design means one thru-hull hole handles both depth and temp, streamlining your setup without compromising data quality.

Engineered for Speed and Durability

Crafted from marine-grade bronze, the B285M withstands the harshest saltwater abuse, resisting corrosion and biofouling over seasons of heavy use. The included high-speed fairing block aligns the transducer perfectly with your hull's deadrise angle—typically 12-20 degrees—reducing turbulence and cavitation at speeds over 20 knots. No more signal loss when you're running to the grounds; this setup keeps readings rock-solid from idle to wide-open throttle.

Boaters with planing hulls appreciate how the fairing's hydrodynamic shape boosts efficiency, potentially shaving fuel burn while preserving sonar performance. It's a smart investment for center consoles, sportfishers, and yachts pushing boundaries offshore.

1kW Power: Penetration Where It Counts

Packed with 1,000 watts of RMS power, the B285M punches through soft bottoms and heavy cover to reveal hidden contours and structure. Pair it with compatible Furuno sounders, and you'll unlock wide-beam coverage for comprehensive bottom mapping alongside narrow-beam precision for individual targets. This balance makes it ideal for everything from reef hunting to bluewater pelagics.

Seamless Compatibility and Installation Insights

With its standard 10-pin connector, integrating the B285M into your existing Furuno ecosystem is straightforward—think TZtouch, NavNet, or DRS-series black box networks. For DIY installers, select a hull location forward of the running gear, away from strakes, and ensure a fairing match to your hull deadrise for optimal beam projection. Professional tips: Bed it in marine sealant, torque to spec, and wet-test before heading out to calibrate.

Pro anglers often highlight its plug-and-play reliability, minimizing downtime and maximizing time on the water. If you're upgrading from an older single-frequency thru-hull, the leap in clarity will transform your electronics suite.

Real-World Performance from Trusted Waters

From Gulf Stream canyons to Pacific seamounts, the B285M earns its stripes where performance matters most. Skippers report consistent marks on swordfish at 600 feet and flawless bottom tracking over rugged terrain. It's not flashy—it's functional, built by Furuno's legacy of innovation since pioneering commercial fishfinders decades ago.