Garmin

Garmin B258 1kW Bronze Thru-Hull Depth/Temp w/FB - 8-Pin

SKU: 43557 · UPC: 753759971892 · MPN: 010-10703-20
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02 · Overview

Garmin B258 1kW Bronze Thru-Hull Depth/Temp w/FB - 8-Pin — Product description

Imagine cruising through choppy offshore waters, confidently tracking fish schools at extreme depths or mapping the seafloor with crystal-clear precision. This rugged bronze thru-hull transducer delivers exactly that, blending high-power sonar capabilities with reliable temperature readings to elevate your boating adventures. Engineered for serious mariners who demand performance without compromise, it cuts through the noise of generic sensors to provide actionable insights on the water.

Superior Deep-Water Detection for Serious Boaters

With its robust 1kW output, this transducer excels in challenging environments where lesser units falter. The dual-frequency setup—switching seamlessly between broader coverage for wide-area scanning and focused beams for pinpoint detail—means you spot structure, baitfish, and bottom contours up to impressive depths. Fishermen targeting trophy species in deep blue water appreciate how the narrow beam angle sharpens bottom definition, revealing subtle drop-offs and wrecks that could hold your next big catch.

Bronze construction stands up to constant saltwater exposure, resisting corrosion better than plastic alternatives. The included fairing block streamlines water flow over the face, minimizing air bubbles and turbulence for consistent readings even at speed or in rough conditions. Paired with integrated temperature sensing, you'll get a full picture of underwater conditions, helping you adjust trolling speeds or bait choices on the fly.

Seamless Integration with Your Marine Electronics

Designed as a drop-in upgrade for compatible chartplotters and sounders, the 8-pin connector ensures plug-and-play simplicity. Its extended cable reach gives installers flexibility, whether you're working on a sleek sportfisher or a sturdy cruiser. This unit thrives on hulls with deadrise angles in the common range, making it versatile for most planing and displacement vessels.

Pro Tips for Optimal Performance

  • Position the thru-hull mount forward of the propeller and strakes to avoid interference, ensuring laminar flow for accurate data.
  • Match the fairing block's angle precisely to your hull's deadrise during install—mismatches can lead to signal loss in turns.
  • Combine with high-definition sonar settings on your display for enhanced target separation, turning raw pings into fishable intel.
  • Regularly inspect the face for marine growth; a clean surface is key to maintaining sensitivity over long trips.

Built for Endurance on the Open Water

Boat owners rave about its longevity in harsh marine settings—from pounding through head seas to enduring tropical heat. Unlike budget transducers that ghost out in deep water or foam up at displacement speeds, this one maintains lock-on reliability. It's the choice for offshore tournaments, long-range cruising, or anyone serious about sonar as a tool for safer, more productive outings.

Enhance your setup by calibrating water temperature offsets for precise baitfish tracking, or layer depth data with GPS charts for custom contour maps. Mariners often pair it with forward-facing sonar for a 360-degree view, but it shines solo on vessels prioritizing depth over side-scan bells and whistles.

Frequently Asked Questions

What kind of boats is this transducer best suited for?

It's ideal for mid-to-large offshore boats like center consoles, sportfishing yachts, and sailboats with deadrise angles between 0 and 26 degrees. Perfect for hulls punching into deep water regularly.

Does it work well at high speeds?

Yes, the fairing block design promotes smooth water flow, reducing cavitation and delivering stable readings up to planing speeds typical for most recreational vessels.

How does the dual-frequency feature help with fishing?

The 50 kHz offers wide-area coverage for locating schools, while 200 kHz provides sharp detail for identifying species and structure—switch based on conditions for maximum effectiveness.

Is installation DIY-friendly for experienced boaters?

Absolutely, with clear instructions included. You'll need basic tools for hull drilling and fairing alignment, but pros handle it in under an hour on most setups.

Can it detect temperature changes accurately?

The built-in sensor provides reliable surface water temps, crucial for thermocline awareness and bait selection. Calibrate seasonally for peak accuracy.

What's the advantage of bronze over plastic transducers?

Bronze offers superior strength and corrosion resistance in saltwater, lasting seasons longer while holding a precise acoustic face for consistent performance.

Will it work with older Garmin chartplotters?

The 8-pin design pairs with many Garmin marine displays supporting 1kW transducers—check your model's sonar specs for compatibility.

Garmin make products that are engineered on the inside for life on the outside. We bring GPS navigation and wearable technology to the automotive, aviation, marine, outdoor and fitness markets. We believe every day is an opportunity to innovate and a chance to beat yesterday. We offer products with essential utility, leading-edge technologies, compelling features, and exceptional ease-of-use to create clear differentiators our customers appreciate and desire.

Garmin 101070320 Attributes

  • Mounting Location: Thru-Hull Mount
  • Number Of Pins: 8 Pin
  • Depth: 1500 To 2200 Feet
  • Power Rating: 1000 Watt
  • Frequency Range: 50/200 kHz
  • Supported Angle: 0 To 26 Degree Deadrise
  • Cable Length: 39 Feet

Garmin 101070320 Features & Benefits

  • Mid-Range 1000 Watt 8-Pin Transducer With A Narrow Beam Is Good For Deep Water And Bottom Definition
  • Transducer Has A Depth Of 1,500 To 2,200 Feet
  • Transducer Kit Comes With Installation Instructions
  • Transducer Supports A 0 To 26 Degree Deadrise
  • Limited 1 Year Warranty

Garmin 101070320 Warranties


B258 1kW Bronze Thru-Hull Depth/Temp w/FB - 8-Pin

Garmin's bronze, thru-hull mount transducer with fairing provides depth and temperature data. This transducer has an operating frequency of 50 or 200 kHz and mounts on a 0-25° deadrise angle.

"The B258 is 25 times more sensitive than a single-element 50\/200 kHz transducer. This 1 kW transducer makes 600 W fishfinders perform like their more powerful big brothers - especially at 50 kHz. How does it do it? The B258 uses Airmar's unique ceramic-element construction. The resulting narrow beams will clearly distinguish individual fish and bottom fish from their habitat at depths down to 670 m."
SKU: NVN-43557
MPN: 010-10703-20
UPC: 753759971892
03 · The numbers

Technical specifications

BrandGarmin
ModelGarmin B258 1kW Bronze Thru-Hull Depth/Temp w/FB - 8-Pin
SKU / MFR#43557

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04 · Before you buy

Frequently asked questions

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05 · Customer voices

Customer reviews