Airmar B175 CHIRP Transducer: Complete Guide for Every Fishfinder Brand

The Airmar B175 is the most widely installed aftermarket CHIRP thru-hull transducer in the offshore fishing world. It's the same element that Garmin, Simrad, Furuno, and other brands use inside their bundled transducers — sold direct so you can spec exactly what you need. This guide covers every B175 variant: frequency bands, tilt options, connector types, and which one to buy for your specific fishfinder.

The B175 Family: H, M, and L

The Airmar B175 comes in three frequency variants, all at 1kW power:

• B175H — High CHIRP (130–210kHz): The most popular. Excellent resolution from the surface to mid-offshore depths (600–800 feet typical operational range). The choice for inshore, nearshore, and offshore day trips.
• B175M — Medium CHIRP (80–160kHz): The versatile all-rounder. More depth penetration than the B175H, better resolution than the B175L. Ideal for anglers fishing 0–1,000 feet across a mix of environments.
• B175L — Low CHIRP (28–60kHz): Built for depth. The B175L maintains bottom contact in canyon fishing, deep-water wrecks, and tilefish drops at 1,000–3,000+ feet. Trades shallow-water resolution for deep-water penetration.

Tilted Element™: Why Tilt Angle Matters

Every B175 variant is available in 0°, 12°, and 20° tilt. This is critical to get right. The transducer element needs to point straight down at cruise speed — not while sitting at the dock. If your hull has deadrise (the angle between the keel centerline and the hull bottom), you need to match that deadrise angle with the corresponding tilt.

Getting the tilt wrong by even 5° reduces your effective bottom contact by 30–50% and creates false returns. Measure deadrise at the planned installation location (typically 12–24 inches aft of the keel centerline) before ordering.

Connector Guide: Ordering the Right Plug

The B175 is the same transducer across all connector variants — only the plug changes. Order the connector that matches your fishfinder brand and you're done. If you're unsure, or if you might upgrade your fishfinder later, order the Mix & Match (no connector) version and add the adapter cable for your current brand separately. This lets you reuse the transducer housing if you switch brands.

Installation Tips

• Housing material: The B175 uses a bronze housing — compatible with fiberglass, wood, and steel hulls. Do not install bronze in aluminum hulls (galvanic corrosion).
• Speed fairing: The B175 does not include a fairing block. For boats that run fast (30+ mph), add an Airmar fairing block to reduce turbulence and improve high-speed performance.
• Depth below hull: The element should sit 0.5–1.5 inches below the hull to ensure water contact when the boat is running. Follow Airmar's installation guide for exact protrusion measurements.
• Sealant: Use Boat Life Life-Calk or equivalent marine sealant — not silicone. Silicone is not water-block rated for below-waterline use.

B175 by Fishfinder Brand

Ordering the right connector is as simple as knowing your fishfinder. Here are the most common pairings we see at BOE Marine:

Airmar B175 High Chirp, 1kW, 0° Tilted Element™, Furuno 10-Pin, DT

SKU: AIR-B175C-0-H-10F | More Info

The Furuno-compatible B175H — 1kW High CHIRP with a 10-pin Furuno connector for direct plug-in with compatible Furuno fishfinder/chartplotters. No adapters needed. 0° tilt for flat-bottomed or minimal deadrise hulls.

Airmar B175 High Chirp, 1kW, 0° Tilted Element™, Garmin 12-Pin, DT

SKU: AIR-B175C-0-H-12G | More Info

Garmin-ready B175H in 8-pin configuration. Plug directly into Garmin GPSMAP and ECHOMAP chartplotter/fishfinder combos without any adapters. The most popular connector option for the B175H in our shop.

Airmar B175 High Chirp, 1kW, 0° Tilted Element™, Navico 9-Pin, DT

SKU: AIR-B175C-0-H-9N | More Info

Navico 9-pin connector for direct compatibility with Simrad NSS, NSO, and B&G Zeus chartplotters. Same 1kW High CHIRP performance as every other B175H variant — just the right plug for your brand.

Airmar B175 High Chirp, 1kW, 0° Tilted Element™, Humminbird 21-Pin, DT

SKU: AIR-B175C-0-H-21HB | More Info

Humminbird 21-pin version of the B175H. Pairs directly with Humminbird HELIX and SOLIX units that support CHIRP. 0° tilt, 1kW High CHIRP, full Airmar performance with native Humminbird connectivity.

Airmar B175 High Chirp, 1kW, 0° Tilted Element™, Raymarine 11-Pin, DT

SKU: AIR-B175C-0-H-11R | More Info

Raymarine-compatible B175H for A-series and Axiom chartplotter users. Same 1kW High CHIRP element as all B175H models, with Raymarine's proprietary connector.

Airmar B175M Bronze 0 Degree Thru-Hull 1kW f/Garmin w/8-Pin Connector

SKU: AIR-B175C-0-M-8G | More Info

The B175M in Garmin 8-pin configuration — Medium CHIRP at 1kW for Garmin users who fish a wider range of depths. More depth penetration than the B175H, better resolution than the B175L. The all-rounder.

Airmar B175L 20° CHIRP Bronze Thru-Hull 1kW - Needs Mix & Match Cable

SKU: AIR-B175C-20-L-MM | More Info

B175L in 20° tilt — ideal for hulls with significant deadrise at the transom or keel. Low CHIRP at 1kW for deep-water offshore fishing. If you need bottom contact at 1,500+ feet, this is your transducer.

Airmar B175H Bronze 0 Degree Thru-Hull 1kW f/Garmin w/8-Pin Connector

SKU: AIR-B175C-0-H-8G | More Info

The B175H in a compact bronze housing variant. Same 1kW High CHIRP performance, same Airmar Tilted Element™ technology. Available in multiple connector and tilt options.

🎣 Expert Advice from Mack Jennings

The B175H in Garmin 8-pin is our single most-requested transducer installation. Paired with a current GPSMAP or ECHOMAP chartplotter, it transforms the sonar picture. If you've been running a plastic transom-mount transducer or even an older bronze thru-hull, the difference is not subtle — it's like going from a flip phone camera to a current-generation smartphone.

One thing customers frequently overlook: the B175 is sold as a transducer only, without a fairing block. If you run above 25 mph regularly, budget for the appropriate Airmar fairing block at the same time. Turbulent water at the transducer face kills high-speed performance, and a fairing block is the fix. We install fairing blocks on most of the B175 installs we do in the shop.

Need help specifying the right tilt angle, connector, or fairing block? Email sales@boemarine.com with your fishfinder model, boat hull material, hull deadrise, and top speed. We'll get you the right order.