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Koo Open Sunglasses



High-quality cycling glasses with easy interchangeable lenses

At every product is thoroughly tested for as long as it takes to get a proper insight into how well it works. Our reviewers are experienced cyclists that we trust to be objective. While we strive to ensure that opinions expressed are backed up by facts, reviews are by their nature an informed opinion, not a definitive verdict. We don't intentionally try to break anything (except locks) but we do try to look for weak points in any design. The overall score is not just an average of the other scores: it reflects both a product's function and value – with value determined by how a product compares with items of similar spec, quality, and price.

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Kask, the helmet sponsor of Team Sky, has launched an eyewear label called Koo, and these Open Sunglasses are the first to be launched under this new brand name. They feature novel rotating arms, large interchangeable lenses and, naturally, they work harmoniously with Kask helmets.

You'd think it would be obvious for a helmet manufacturer to also turn out its own eyewear, but surprisingly few of the leading helmet brands make their own glasses. Giro did for a brief period, while the most recognisable eyewear brand, Oakley, has never dabbled in the helmet market.

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The sunglasses are made in Italy and the frames have a unique rotating arm design. There's a small hinge at the elbow – flick it up and the arm can rotate away for storage. An added benefit is that it lets you rotate the angle of the lenses away from the face slightly – useful as a means of reducing fogging on longer climbs, though I still found it easier to simply pull the glasses forward on the nose.

Kask Open Sun Glasses - folded.jpg

The arms are lined with a rubber material to help grip the temples, and the rubber nosepieces can be adjusted easily to fit different nose sizes. There's a smaller nosepiece included in the box so you can really dial the fit, which I found to be really good, although they're a little less secure feeling on the head compared with Oakley's Jawbreaker. That said, they never actually slipped out of position during even the sweatiest riding.

Kask Open Sun Glasses - back.jpg

Kask/Koo isn't messing around with the lens quality and has gone to the most recognisable name in the market, Zeiss. As you'd expect, the quality is superb with excellent clarity and they compare extremely well with other high-end cycling glasses. You get two lenses in the box, helping to justify the high price. The tinted lens is just right for everything from overcast to bright, sunny days, with the clear lens ideal for evening rides and night rides.

Kask Open Sun Glasses - spare lens.jpg

Changing lenses is pretty easy – simply rotate the small retaining tabs and pop the lenses out – but it's impossible to carry out the change without getting grubby fingerprints all over the lenses, unlike with Oakley's Jawbreaker design. You'll need to give them a clean using the supplied cleaning wipe or the soft bag they come with.

Kask Open Sun Glasses - boxed.jpg

The lens is wide and tall and provides really good coverage as well as minimising frame intrusion to your vision, especially when in the drops or tucking your head down low. They're not quite in the same ballpark as the Jawbreakers, with a little more frame intrusion noticeable, but it's a lot less than many regular eyewear designs. For regular upright cycling, they are just fine and vision is unobstructed.

> Buyer's Guide: 21 of the best cycling glasses

Of course, the glasses have been designed to play well with Kask helmets, as you'd expect. I tested them with a Protone helmet and the fit was flawless, with no conflict with the retention strap. I also tried them with other helmet brands, including Giro and Lazer, and encountered no problems there either.

Kask is aiming high with these Open glasses, both in terms of performance and price. Judged on the former they live up to the high expectations and deliver a comfortable fit, easy lens change, good clarity and generous lens coverage. They are compatible with most helmet brands so you don't need to own a Kask helmet to be interested in them. They're available in a wide range of colours, and you get two lenses and a large protective case all helping to justify the high price. It's not the highest we've ever seen, either – you can certainly pay a lot more – but on the flip-side, you can pay a lot less.


High-quality cycling glasses with easy interchangeable lenses test report

Make and model: Koo Open Sunglasses

Size tested: One size

Tell us what the product is for, and who it's aimed at. What do the manufacturers say about it? How does that compare to your own feelings about it?

The first KOO collection is designed specifically to work seamlessly with KASK cycling helmets.

Kask KOO open glasses also feature easily-removable, interchangeable lenses for year-round optimum vision when cycling. The design also includes an 'Airflow Active System' which means the lenses can be tilted at three different angles to adjust the position of the glasses on your face. Flexible temples should also improve the fitting without interfering with comfort.

The sunglasses are constructed of polycarbonate with each component 100% made in Italy. Attention to detail has been paramount with lenses manufactured by the renowned lens maker Zeiss.

Kask Koo Open Glasses include two sets of lenses. One darker lenses to match glasses frame and the other an extra clear

Tell us some more about the technical aspects of the product?


Carl Zeiss Lens

frames have a unique flip-in arm design

Adjustable nose bridge

One clear lens supplied

Photochromic available as an extra lens

Made in Italy

Rate the product for quality of construction:
Rate the product for performance:

A large and generous lens coverage with little frame intrusion when racing in the drops.

Rate the product for durability:

I've sweated, travelled abroad with them and dropped them, and they've survived everything just fine.

Rate the product for weight (if applicable)
Rate the product for comfort (if applicable)

A very comfortable frame design with adjustable nosepiece.

Rate the product for value:

While expensive they're not the most expensive we've seen, but you can certainly pay a lot less. The inclusion of two lenses and a large protective case helps justify the price.

Tell us how the product performed overall when used for its designed purpose

Provided good coverage and comfort.

Tell us what you particularly liked about the product

Sharp lens quality, interchangeable lenses and easy to fold away.

Tell us what you particularly disliked about the product

Quite pricey.

Did you enjoy using the product? Yes

Would you consider buying the product? Maybe

Would you recommend the product to a friend? Probably

Use this box to explain your score

It's a very impressive debut eyewear product from the helmet manufacturer.

Overall rating: 8/10

About the tester

Age: 31  Height: 180cm  Weight: 67kg

I usually ride:   My best bike is:

I've been riding for: 10-20 years  I ride: Every day  I would class myself as: Expert

I regularly do the following types of riding: road racing, time trialling, cyclo-cross, commuting, touring, mountain biking

David worked on the tech team from 2012-2020. Previously he was editor of and before that staff writer at RCUK. He's a seasoned cyclist of all disciplines, from road to mountain biking, touring to cyclo-cross, he only wishes he had time to ride them all. He's mildly competitive, though he'll never admit it, and is a frequent road racer but is too lazy to do really well. He currently resides in the Cotswolds, and you can now find him over on his own YouTube channel David Arthur - Just Ride Bikes

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