INBOUND: Duotone Unit SLS Concept Blue

Duotone’s latest Unit wing enters the scene, as part of their “Concept Blue” range, boasting multiple eco-friendly features. We caught up with wing designer Ken Winner for the full rundown on this fresh addition to the Duotone wing family…


This new version of the Unit comes as SLS Concept Blue. For those who aren’t aware of what these terms indicate, could you please give us a brief overview?

The SLS Concept Blue version has two distinctive features. Firstly it incorporates undyed fabrics, recycled plastic parts and bio-based bladders to reduce its environmental impact. Secondly, whilst retaining the deep, powerful, robust profile depth of the standard Unit, the SLS has a slightly smaller diameter, yet still quite stiff leading edge in Aluula and Penta TX materials. 

So that is a little band of Aluula we spy in the mid-section?

The center of the leading edge of a wing has the greatest bending loads, so in the original Unit we used a stiffer, heavier, 240-gram Dacron in the center panels. These stiffer panels do a good job of minimizing leading edge bend without adding too much weight. In the SLS Unit we replace those 240-gram panels with 82-gram Aluula, which gives us the same stiffness at a lower weight. The Penta TX used in the rest of the frame is stiffer compared to our 160-gram Dacron we’re using in our original Unit. Together these two materials make for a great stiffness at a reasonable cost.

And now to the practicalities – tell us who’s gonna love getting out on it, and why…

The Unit started as a surf-oriented wing but ended up being used for everything from surf to downwinding, to freestyle, racing and general cruising. We have now focused it more on its overall flying performance and power delivery, while improving its surf and downwind abilities. I should point out that a new wing, coming out in spring, takes over as the dedicated surf and downwind wing, which frees the Unit even more to be, as I said  , the do-it-all from surfing waves to freestyle and cruising. And I think that’s what people like about it – it feels and works good in so many different scenarios.

There seem to be less canopy panels than the previous model, why has this design decision been made?

We’re always looking for ways to distribute load on the canopy panels efficiently, and always looking for ways to build wings as efficiently as possible. This means experimenting with everything. Up to a point, fewer panels can lead to better performance, durability and efficiency in manufacturing. Beyond that point, we get a reverse of those benefits. The panel layout of the new Unit is an instance of us looking for the optimum compromise between complexity and simplicity. This worked well on the 2024 Slick, so we carried it forward to the 2025 Unit. That said, there’s no reason to think we’ll carry it forward in other wings in the future because we’re learning all the time about what works and what doesn’t. Ideas that didn’t work two years ago can be re-examined at any time and can then be found to work in combination with other design ideas. 

Would you say the Unit has been the most popular wing in the range? If so, why do you think that’s the case?

Yes definitely, for three main reasons. Firstly it has been a very versatile wing with good performance in a large range of disciplines. Secondly it was the first wing with well-designed rigid handles and a lot of riders really liked these. A boom-equipped wing is more intuitive and also a bit lighter, so now we’re offering both options with our new Fusion Handles and Fusion Boom on the Unit 25. The third reason the Unit has been popular is because it has a longer season because of the time of year that it is presented to the market.

How does the Unit SLS Concept Blue fare alongside the D/LAB version? Why would customers pick one over the other?

The SLS has a very powerful, grunty feeling and a somewhat lower price. The D/LAB has a more refined feel, a more speed-oriented feel. It’s the wing that feels super stable and fast, and which works well for the more advanced rider. At the same time, I should point out that the lower weight of the D/LAB is a nice benefit even for riders who are not very advanced. My wife for example prefers the lower weight of the D/LAB Units. 

Which board is the optimum pair-up with the Unit SLS Concept Blue?

It depends a bit on the conditions and riding preferences – I would say the Sky Style SLS and the new Skybrid SLS are probably the most popular matches. But you can use the Unit SLS on any board of the range really, as this wing model covers so many disciplines.

There’s been a lot of releases from Duotone recently. Name us a few other highlights of the range.

The Unit D/LAB remains the top performer of the wing range. In terms of boards the entire range has been redesigned, the highlight surely being the Skybrid SLS, which is very well received amongst all type of riders for its efficiency with easy access to its performance. The 2025 Sky Style SLS is our high-performance wingfoil board for freestyle and waves and comes with reduced weight, refined outline, and optimized volume distribution for improved stability. The Crush SLS isdesigned for prone foiling and the new Downwinder SLS and Downwinder Slim SLS are built for maximum efficiency, offering everything from entry to top-level downwind foiling performance.

In terms of foils the Glide 2.0 D/LAB Foil has just entered the market with really great feedback. It delivers exceptional speed, pump and glide performance across all foiling disciplines and it turns really intuitively too. Of course there’s also the screw-on SLS version of the Glide 2.0. The Hyperglide D/LAB is a top-tier addition to our 2025 foil line-up, built for pure efficiency and speed in downwinders. Finn and Jeffrey Spencer finished second and fifth on protos of these foils in this year’s Downwind Triple Crown in Hawaii. Our new Mast Slim 2.0 D/LAB is another project our team has put a lot of work in. Every size from 76 to 84 to 94 cm is finely tuned for each individual use case and you can really feel the difference. We also have some more interesting products coming up next spring. 

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