Ultrasonic Antifouling
HDi Series - The Next Generation of Hull Protection is Here - Advanced Ultrasonic Antifouling Protection For Recreational and Light-Watercraft
Smarter. Stronger. Connected.
Hull Shield’s HDi Series redefines antifouling for recreational and light-watercraft with unmatched power, intelligent control, and smart technology. Engineered to outperform all competitors, HDi delivers 100% more ultrasonic power, exclusive INTELI-BOOST™ and INTELI-SENSE™ technologies, and seamless app/website connectivity. Keep your hull cleaner for longer, reduce maintenance costs, and enjoy a smarter, more efficicent boating experience — all with automatic, eco-friendly antifouling protection.
Hull Shield HDi systems work 24/7 to prevent bio-fouling on hulls, drives, rudders, thrusters, and more. By combining powerful ultrasonic pulses with intelligent controls, HDi extends the life of your bottom paint, improves fuel efficiency, and saves you thousands in maintenance costs over the life of your vessel. Upgrade to HDi — and spend less time & money on maintenance and more time on the water.
Ultrasonic Protection for All Boat Types – Power Boats, Sailboats, Catamarans, Yacht, & More. Fully automatic protection that adapts to your vessel. HDi ultrasonic antifouling systems can be used as stand-alone units or combined to protect boats of any size, with enhanced range and intensity thanks to Hull Shield’s INTELI-BOOST™ technology.
Click on an all new for 2026 HDi System below to learn more and pre-order!
HDi1
Ultrasonic Antifouling System
For Hulls, Drives, & More
The HDi1 is a single-transducer unit engineered as a stand-alone system to provide powerful antifouling protection for hulls, drives, rudders, stabilizers, and more.
This unit can also be combined with other Hull Shield systems to extend protective range and/or anti-fouling intensity.
This system is equipped with a single transducer emitter used to generate the ultrasonic signals which disrupt marine fouling.
This system provides an automated ECO low-power mode compatible with solar & wind power supplies.
The HDi series offers an increased efficiency profile that is capable of delivering nearly double the power directly to the transducers when compared to prior versions.
INTELI-BOOST™ for synchronized transducer power boost
INTELI-SENSE™ remote monitoring with app/text/email alerts
Bluetooth, WiFi, and wireless connectivity
LED indicators per port for instant status checks
App/website controls: remote power on/off, selective frequency profiles, power usage graphs, customizable power profiles (Solar, Wind, Max, Eco, Day, Night)
HDi2
Ultrasonic Antifouling System
For Hulls, Drives, & More
The HDi2 is a two-transducer unit engineered as a stand-alone system to provide powerful antifouling protection for hulls, drives, rudders, stabilizers, and more.
This unit can also be combined with other Hull Shield systems to extend protective range and/or anti-fouling intensity.
This system is equipped with two transducer emitters used to generate the ultrasonic signals which disrupt marine fouling.
This system provides an automated ECO low-power mode compatible with solar & wind power supplies.
The HDi series offers an increased efficiency profile that is capable of delivering nearly double the power directly to the transducers when compared to prior versions.
INTELI-BOOST™ for synchronized transducer power boost
INTELI-SENSE™ remote monitoring with app/text/email alerts
Bluetooth, WiFi, and wireless connectivity
LED indicators per port for instant status checks
App/website controls: remote power on/off, selective frequency profiles, power usage graphs, customizable power profiles (Solar, Wind, Max, Eco, Day, Night)
HDi3
Ultrasonic Antifouling System
For Hulls, Drives, & More
The HDi3 is a three-transducer unit engineered as a stand-alone system to provide powerful antifouling protection for hulls, drives, rudders, stabilizers, and more.
This unit can also be combined with other Hull Shield systems to extend protective range and/or anti-fouling intensity.
This system is equipped with three transducer emitters used to generate the ultrasonic signals which disrupt marine fouling.
This system provides an automated ECO low-power mode compatible with solar & wind power supplies.
The HDi series offers an increased efficiency profile that is capable of delivering nearly double the power directly to the transducers when compared to prior versions.
INTELI-BOOST™ for synchronized transducer power boost
INTELI-SENSE™ remote monitoring with app/text/email alerts
Bluetooth, WiFi, and wireless connectivity
LED indicators per port for instant status checks
App/website controls: remote power on/off, selective frequency profiles, power usage graphs, customizable power profiles (Solar, Wind, Max, Eco, Day, Night)
HDi4
Ultrasonic Antifouling System
For Hulls, Drives, & More
The HDi4 is a four-transducer unit engineered as a stand-alone system to provide powerful antifouling protection for hulls, drives, rudders, stabilizers, and more.
This unit can also be combined with other Hull Shield systems to extend protective range and/or anti-fouling intensity.
This system is equipped with four transducer emitters used to generate the ultrasonic signals which disrupt marine fouling.
This system provides an automated ECO low-power mode compatible with solar & wind power supplies.
The HDi series offers an increased efficiency profile that is capable of delivering nearly double the power directly to the transducers when compared to prior versions.
INTELI-BOOST™ for synchronized transducer power boost
INTELI-SENSE™ remote monitoring with app/text/email alerts
Bluetooth, WiFi, and wireless connectivity
LED indicators per port for instant status checks
App/website controls: remote power on/off, selective frequency profiles, power usage graphs, customizable power profiles (Solar, Wind, Max, Eco, Day, Night)
HDi6
Ultrasonic Antifouling System
For Hulls, Drives, & More
The HDi6 is a six-transducer unit engineered as a stand-alone system to provide powerful antifouling protection for hulls, drives, rudders, stabilizers, and more.
This unit can also be combined with other Hull Shield systems to extend protective range and/or anti-fouling intensity.
This system is equipped with six transducer emitters used to generate the ultrasonic signals which disrupt marine fouling.
This system provides an automated ECO low-power mode compatible with solar & wind power supplies.
The HDi series offers an increased efficiency profile that is capable of delivering nearly double the power directly to the transducers when compared to prior versions.
INTELI-BOOST™ for synchronized transducer power boost
INTELI-SENSE™ remote monitoring with app/text/email alerts
Bluetooth, WiFi, and wireless connectivity
LED indicators per port for instant status checks
App/website controls: remote power on/off, selective frequency profiles, power usage graphs, customizable power profiles (Solar, Wind, Max, Eco, Day, Night)
HDi8
Ultrasonic Antifouling System
For Hulls, Drives, & More
The HDi8 is a eight-transducer unit engineered as a stand-alone system to provide powerful antifouling protection for hulls, drives, rudders, stabilizers, and more.
This unit can also be combined with other Hull Shield systems to extend protective range and/or anti-fouling intensity.
This system is equipped with eight transducer emitters used to generate the ultrasonic signals which disrupt marine fouling.
This system provides an automated ECO low-power mode compatible with solar & wind power supplies.
The HDi series offers an increased efficiency profile that is capable of delivering nearly double the power directly to the transducers when compared to prior versions.
INTELI-BOOST™ for synchronized transducer power boost
INTELI-SENSE™ remote monitoring with app/text/email alerts
Bluetooth, WiFi, and wireless connectivity
LED indicators per port for instant status checks
App/website controls: remote power on/off, selective frequency profiles, power usage graphs, customizable power profiles (Solar, Wind, Max, Eco, Day, Night)
Continuous Antifouling Protects your Vessel from Fouling.
HDi ultrasonic antifouling uses advanced sound waves to physically repel fouling organisms away from the surface before they can permanently attach, while higher-frequency bands disrupt their reproductive cycles.
Hull Shield systems operate siminlar to a stereo and speakers. The controller sends ultrasound signals to transducers attached to the hull or running gear, the ttransducers receive the high-frequency signals, transforming them into ultrasonic pulses.
Each pulse creates a microscopic shockwave that runs across the hull and drive gear. These ultrasonic waves work to ablate, loosen, and repel foulding which is contacting the hull and drive surfaces. When used in conjunction with an ablative bottom paint, Hull Shield systems are the most effective and long-term antifouling solution available.
Exclusive HDi Advancements:
100% Stronger Power: 60 watts vs. competitors’ ≤30 watts for superior fouling prevention.
INTELI-BOOST™ Technology: Amplify protection with synchronized transducers. This proprietary, patent-pending feature creates constructive interference for a targeted power boost, ideal for drives and props, and high growth areas, delivering up to 230% more effective fouling prevention without extra energy draw.
INTELI-SENSE™ Remote Monitoring and System Control: Stay connected with patent-pending real-time system health checks and instant alerts via app, text, or email. Manage your system anytime — turn it on/off, track power usage with historical graphs and charts, select from preset profiles (Solar, Wind, Max, Eco, Night), or create fully customized power profiles based on current usage and schedules for seamless, efficient operation.
INTELI-TUNE™ Selective Frequencies: Patent-pending feature to precisely tune frequency bands to target specific marine growth types. Fine-tune your system’s ultrasonic output with adaptive frequency control, focusing protection where it matters most – in the waters you actually boat – delivering optimized antifouling performance for the growth in your environment.
INTELI-CONNECT™ Smart Connectivity: Bluetooth, WiFi, and app/website controls. Seamlessly integrate HDi into your digital ecosystem. Use Bluetooth for local control, WiFi for network access, or wireless for ultimate flexibility—HDi is your smart antifouling solution.
Ultrasonic Antifouling Hull Coverage
Stay cleaner for longer while extending the functional lifespan of your bottom paint.
Each transducer provides approximately 200sqft of protected underwater surface area. A rough estimate of your underwater surface area can be calculated by doubling your draft, adding it to your beam, then multiplying by your length (use overall hull length). The below graphs can be used as a guide for a vessels overall length calculations:
Ultrasonic Antifouling for Drives
Not just for hulls – Hull Shield can protect your drives and running gear too!
Drives are isolated from the hull by motor mounts, gaskets, seals and other insulative materials that block ultrasound from passing to shafts, props, and rudders. Because of this, the drive system requires dedicated transducers to gain the most benefit from ultrasonic anti-fouling. Inboards, pods, sterndrives, and sail-drives can all be fitted with a transducer to enable full anti-fouling protection. Rudders are isolated from the hull in the same way as the drives and also require a dedicated transducer.
One transducer per isolated part delivers optimal results for most vessels under 55 feet. Examples of isolated parts are drive shaft & props, rudders, exterior engine brackets, struts, & stabilizers. Because these parts are isolated from the hull and each other, a transducer is required for each independent part.
On larger vessels with 3″ wide or larger shafts & larger props or larger pods drives (IPS D8 and D13, larger Zeus models), two transducers utilizing HDi’s INTELI-BOOST™ enhances protection are used for these areas, ensuring larger shafts, props, and pods also stay fouling-free.
Curious How HDi Outshines the Competition and Legacy Systems? Dive into the Details Below!
HDi Comparison Table
| Feature | HDi Series | HD Legacy Series | Competitors |
|---|---|---|---|
| Power Output | 60 Watts | 30 Watts | ≤30 Watts |
| INTELI-BOOST™ | ✅ | ❌ | ❌ |
| INTELI-SENSE™ | ✅ | ❌ | ❌ |
| INTELI-TUNE™ | ✅ | ❌ | ❌ |
| App Connectivity | ✅ | ❌ | ❌ |
| Port & Status LED Indicators | ✅ | Minimal | ❌ or Minimal |
| Audible Fault Alert | ✅ | ✅* | ❌ or Minimal |
| Adjustable Feet (on select models) | ✅ | ❌ | ❌ |
| Selective Frequency Profiles | ✅ | ❌ | ❌ |
| Remote Monitoring & Alerts | ✅ | ❌ | ❌ |
* all HD Series have an audible alert speaker except the HD-1
Hull Shield™, HDi™, INTELI-BOOST™, INTELI-SENSE™, INTELI-TUNE™, and INTELI-CONNECT™ are trademarks of Hull Shield. Patents pending.
HDi systems are available in dedicated 12-volt and 24-volt configurations — each engineered from the ground up for optimal performance at its native voltage.
Many so-called “12V/24V” systems on the market simply use internal converters to step 24V down to 12V, effectively running as a 12V system regardless of input. Hull Shield’s 24V models are true 24-volt systems, delivering higher efficiency, cleaner signal output, and reduced heat generation. It’s another example of Hull Shield’s commitment to authentic engineering – not shortcuts.
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Benefits of Ultrasonic Antifouling
Continuous Antifouling
Hull Shield systems effectively work 24/7 to repel most types of marine fouling.
Improve Performance
A clean hull has less drag, improved fuel efficiency, and increased top-end speed.
Save Money & Time
Spend less money and time with fewer haul-outs, bottom painting, and abrasive cleaning.
Easy Installation
Installation is straight-forward, easy and does not require special tools.
Environmentally Friendly
Use less applications of toxic bottom paint while reducing environmental impact.
Increase Resale Value
Boats having automated anti-fouling hardware have increased resale value.
About Hull Shield
Ultrasonic Antifouling - How it Started
Discover the journey of Hull Shield – from problem to solution. Hull Shield ultrasonic antifouling products were developed to help boat owners just like you.