Duotone Foil Assist
Experience the pure ride feel of foiling, now with electric assistance. The Duotone Foil Assist is an electric assist system for foils. It features a waist-worn battery and a mast-integrated motor. With 33 kg of thrust and 35 to 60 minutes of range, your board stays light and maneuverable, just like a classic foil, but with an added boost.
Presented by Cyril Coste and Greg
The Foil Assist in Action
The essentials in 30 seconds
- Light assistance: approximately 6.3 kg total (waist-worn battery, not on the board).
- Range: 35 to 60 min depending on use, recharges in 45 min.
- Power: 33 kg of thrust (324 N).
- Air travel: LiPo batteries 159.6 Wh (under the 160 Wh limit).
- Compatibility: 11 foil brands and more (F-One, Axis, Gong…).
- Price: starting from €4,799.
What is the Duotone Foil Assist?
The Duotone Foil Assist is not an eFoil (autonomous electric foil). This electric assist amplifies your foiling experience without altering its essence. The motor helps you with take-off, relaunching after a fall, or maintaining speed in light wind areas. Once you're flying, you cut the assist and rediscover the pure ride feel of a classic foil.
Designed by Cyril Coste, a former French kite pro and founder of Takuma, the Foil Assist was born from a simple frustration: losing too much time paddling, pumping, and waiting for the wind. His solution is an ultra-light system that integrates naturally with your existing setup.
The key concept: the battery is worn at the waist, not on the board. As a result, your board remains light and maneuverable, just like a traditional foil. You keep your ride feel, with a boost available when you need it.
How Does It Work?
The system consists of three interconnected elements, plus integrated safety features:
The motorized mast
The motor is integrated directly into the mast, with invisible internal cabling. The folding propeller deploys instantly upon activation and folds back when stopped to minimize DRAG. Motor position: 17 cm below the plate (AL and D/LAB versions). Note: the Cruise version (motor at the bottom of the mast) is ideal for beginners and an introduction to electric foiling, but it is not suitable for Foil Assist as it limits the surfing sensations.
The battery harness
Two LiPo batteries, each 159.6 Wh, are worn in a waist harness. The fabric is buoyant to compensate for the weight in the water. It features a magnetic connection and quick-release safety. The weight (approximately 3.7 kg) is quickly forgotten after a few sessions.
The Ring Watch remote
A ring on your finger and a watch on your wrist. Your hands remain free to paddle, duck-dive, or hold your wing. Double-click to start, +/- to adjust power. Two modes: Standard (5 speeds) and Boost (7 speeds).
Integrated safety features
The folding propeller automatically retracts. The motor cuts off in case of signal loss or a fall. A double-click is required to start, preventing accidental activation. The harness has a quick-release. Optional propeller protection is available.
Duotone offers a series of "How To" videos for assembly, care, and use: see the Duotone YouTube channel.
The Versions: AL and D/LAB
Duotone offers two recommended configurations for the Foil Assist. There's also the Cruise version, which is specifically designed for beginners.
| Version | Main Use | Mast | Compatibility | Kit price |
|---|---|---|---|---|
| AL | Allround: wing, prone, downwind, pump | Alu 84 cm | 11+ brands (adapters) | €4,799 |
| Cruise | Beginners, introduction, eFoil (not suitable for Foil Assist) | Alu 80 cm (motor at the bottom) | 11+ brands (adapters) | €4,799 |
| D/LAB | Performance: surf, prone, downwind racing | HM Carbon 84 cm | Duotone + Armstrong only | €5,999 |
Our recommendation
The AL kit is the perfect choice for 80% of Foil Assist riders. For experts who demand the absolute lightest and most responsive setup, the D/LAB is the way to go. The Cruise is ideal for beginners and those just getting into electric foiling, thanks to its mast-bottom propulsion for added stability. It limits the true surf feel. This makes it unsuitable for Foil Assist.
2027 Range: What's New
Duotone just announced three 2027 Foil Assist sets. All of them share some key upgrades: 10 Ah batteries (up from 7 Ah in the 2026 range), the eHarness 2.0, and a new 3-blade propeller.
- Foil Assist Set 10A AL 2.0: This set features an 84 cm aluminum mast, with the motor positioned 17 cm below the plate, priced at €5,299.
- Foil Assist Set 10A D/LAB 2.0: Step up to an 84 cm carbon mast with this set. The motor position remains the same, and it retails for €6,499.
- Foil Assist HT Set 10A D/LAB: This High Torque set drops the motor to 21 cm below the plate, giving you more torque for take-off. It's available for €6,799.
GlissEvolution public prices are current as of October 21, 2026. Product sheets will hit the shop when stock arrives. Contact us to reserve yours. The 160 Wh airline limit mentioned in this article applies to the 2026 7 Ah batteries. For the new 10 Ah batteries, we'll confirm capacity before your trip. The 2026 sets listed below are still available for purchase.
Complete kits
All Duotone Electric Foil Assist complete kits:
Duotone Foil Assist Set AL 2026
4,799.00 €
Duotone Foil Cruise Set AL 2026
4,799.00 €
Duotone Foil Assist Set D/LAB 2026
5,999.00 €
Duotone Foil Assist Mast AL Complete Set
4,799.00 €
Duotone Foil Cruise AL Complete Set
4,799.00 €
The masts
Motorized masts are also available individually:
Duotone eMAST AL SET
2,449.00 €
Duotone eMAST D/LAB SET
3,649.00 €
Duotone eMAST AL CRUISE SET
2,449.00 €
Compatibility: will it work with my foil?
The AL mast works with over 11 brands. You'll need fuselage adapters, which are sold separately.
Duotone, Armstrong, F-One, Axis, Gong, Lift, North, Code, SAB, AFS, KT, and others on request.
Board compatibility: This system is compatible with all boards featuring standard US rails. For optimal performance, Duotone Midfish boards (38 L to 78 L) are specifically designed for Foil Assist. They include integrated cable routing and a mid-length shape that's perfect for take-off.
D/LAB warning: The carbon mast is only compatible with Duotone (3BS connection) and Armstrong (dedicated adapter) foils.
Who is it for?
Beginners
Electric assist makes take-offs a breeze and helps you recover from mistakes. You'll spend less time frustrated and more time flying. For the full Foil Assist ride feel, we recommend the AL and D/LAB versions.
Intermediates
Enjoy longer sessions and expand your riding conditions, even in light wind or flat water. You'll get quick power delivery after a fall. Accelerate your technical progression with more time flying and more practice.
Experts
This system lets you ride smaller, more technical foils. Explore previously inaccessible spots. Go on longer downwinds. Recover between waves without getting exhausted.
Hadou Brunner's Review
Hadou Brunner has been riding foil assist for over two years, experimenting with a huge variety of gear. He put the entire new range through its paces on the water, with one main question: what's the real difference when you carry the batteries on your body instead of on the board? We've summarized his verdict without altering his insights. Big thanks to Hadou, and be sure to watch his full video to support his channel.
Video Review: Hadou Brunner
Weight on the Belt
Most systems keep the motor and batteries on the board, or just underneath. Duotone, however, keeps the motor in the mast and puts both battery into the eHarness. For Hadou, this means the weight becomes part of your body, like an extension of your muscles. Everything below the belt feels like a normal surf foil setup. The board itself feels significantly lighter. Pumping becomes more intuitive, and the foil loses any unwanted inertia in turns. This is the standout feature for him.
The Notched Remote
This was the biggest adjustment for Hadou. You can't feather the pressure like a trigger. When coming out of a wave, you need to click the remote several times to get back up to speed. He got used to it, but it's still less intuitive. The receiver, housed in the belt, never gets submerged, so signal loss isn't an issue. Duotone also kept it simple with no app required.
Boards and Foils Used
The Midfish 2026 gets you up and riding early and maintains excellent glide. Hadou even used the 5'2 38-liter for parawing. The real surprise was the Crush SLS in 27 liters, his favorite surf foil board this year. It takes off just as early as the Midfish and lets you pump for longer. For foils, he used the Crest D/Lab 800 on flat water and switched to the 675 when the downwind conditions picked up.
Take-off and Range
During take-off, you'll notice a pitching effect that you control by leaning forward, similar to a Foil Drive. When the hull touches the water, there's no motor under the board to snag. At 62 kg, Hadou takes off at speed 5 with the two-blade aluminum propeller. In a flat-water eFoil test, he got almost an hour of ride time, covering 10 km. That range extends even further when you're catching and reconnecting waves. The key is to work with the elements and conserve the motor.
Duotone Foil Assist or Foil Drive?
These two systems are designed for different riders. The Duotone puts the weight on your body, keeping the board light for surfing and pumping. The Foil Drive Assist MaxIt features larger batteries, so you get more range for longer motor-powered sessions. This comes with a bit more board weight. If you're after pure eFoil, go with the Foil Drive. If you want to keep that leg-pumping feel, the Duotone is your choice. Our Foil Drive Assist Max review dives into the other option in detail.
Real-World Feedback
What riders who've tested it are saying:
| Actual range | Expect 45 to 60 minutes in mixed use. A 75 kg rider on a 900 cm² foil reports around 1 hour when downwinding. |
| Weight-to-size ratio | You'll get used to it in just 2 to 3 sessions. The floating harness does a great job of compensating in the water. |
| Feel | With the motor off, it feels exactly like a classic foil. There's no perceptible drag. |
| Remote control | The ring + watch system takes a few sessions to feel natural, but then it becomes instinctive. |
| Value for money | The price is comparable to the Foil Drive Gen2, but you get an integrated aluminum mast. |
Sources: Official Duotone specifications, Seabreeze forums, authorized dealer feedback.
Care
The Foil Assist is designed for simple care:
- After each session: Rinse the mast and motor with fresh water.
- Regularly: Apply dielectric grease to the connectors.
- Battery storage: Keep batteries between 40% and 60% charge (use the Smart Charger's discharge function).
- Battery life: Expect 300 to 500 cycles depending on care (3 to 5 years of normal use).
- Repairs: This is a self-repairable system, and it comes with a tool kit.
Midfish boards: Designed for Foil Assist
Two versions are available to suit every rider's profile.
Midfish (carbon): The performance benchmark
This mid-length board was specifically developed for the Foil Assist. It features full carbon construction with PVC reinforcement in the stance area. Available in sizes: 5'2-inch (38 L), 5'5-inch (48 L), 5'8-inch (58 L), 5'11-inch (78 L). The narrow mid-length shape, low rocker, and fishtail deliver ultra-fast take-offs, maximum lightness, and incredible responsiveness. Ideal for prone, downwind, wing, and freeride. Perfect for intermediate to expert riders who demand performance and versatility.
Midfish Air (inflatable): Safety and transport
This inflatable version is perfect for beginners and for travel. It is also suitable for schools and rentals. It features Fusion Technology construction with a rigid carbon plate. Size: 6'10-inch × 22½" (115 L). The stable mid-length shape and generous volume make it impact-resistant, compact for travel, and comfortable. Great for learning, family fun, schools, and travel.
Duotone Midfish Air 2026
999.00 €
| Feature | Midfish (carbon) | Midfish Air (inflatable) |
|---|---|---|
| Construction | Full carbon + PVC | Fusion Technology + carbon plate |
| Weight | Ultra-light (3 to 4 kg) | Lightweight for an inflatable (approx. 6 kg) |
| Transport | Classic bag | Wheeled backpack (compact) |
| Impact resistance | Standard (carbon) | Excellent (inflatable) |
| Level | Intermediate to expert | Beginner to intermediate |
| Price | from €1,299 | €999 |
The ultimate Foil Assist
The Midfish's fishtail shape gives you direct access to the battery harness cable. Its advanced foil box position ensures balanced take-offs and a light touch. These boards also perform perfectly without electric assist.
Tested and approved by the GlissEvolution team
Our field expertise guides your choice. Based in La Baule, we test every product before recommending it. Our team rides wing, prone foil, and downwind daily.
Frequently Asked Questions
Is the Foil Assist an eFoil?
No. The eFoil is 100% motor-powered. The Foil Assist provides temporary assistance: you use it for take-off or to re-accelerate. Then you switch it off and get back to the feel of a classic foil.
Is it compatible with my board?
Yes, if it has standard US rails. Duotone Midfish boards are optimized for the system, but it's not mandatory.
What is its range?
35 to 60 minutes, depending on your weight, foil size, and how intensely you use it. A full recharge takes 45 minutes with the Smart Charger. Tip: a second set of batteries lets you keep riding.
Do I need to know how to foil?
No, that is the whole point. The Foil Assist makes learning easier by making take-off more accessible. Both the AL and D/LAB versions suit all skill levels.
Can I take it on a plane?
Yes. The 159.6 Wh batteries are below the 160 Wh limit most airlines allow in the cabin. This is a major advantage for traveling riders.
What is the price of a complete kit?
The AL kit starts at €4,799, and the D/LAB at €5,999. These prices include the motorized mast, harness, 2 batteries, remote, and charger.
Is my F-One / Axis / Gong foil compatible?
Yes, with the AL mast and the corresponding fuselage adapter (sold separately). The D/LAB carbon mast is only compatible with Duotone and Armstrong.
What care is required?
Rinse with fresh water after each session. Apply dielectric grease to the connectors. The system is self-repairable with the included tool kit.
Why buy from GlissEvolution?
- Double expertise: As authorized Foil Drive and Duotone retailers, we understand both systems. We provide objective advice to help you choose.
- After-sales support and workshop: With 15 years of experience in electric motorization through Mobility Evolution, we guarantee expert diagnosis and repair.
- Available stock: We stock complete kits, spare parts, batteries, and accessories. Based in France, we offer 24-48 hour delivery.
- Rider advice: We ride wing, surf foil, and downwind. We use the gear we sell.
Ready to make the switch to Foil Assist?
We'll help you choose the right version (AL, D/LAB, or Cruise) and the correct adapters for your foil and riding style.
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Specifications are based on official Duotone documentation and our field tests. Indicative prices for 2026 are subject to change. Always use the electric foil in compliance with local regulations and safety rules.
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