Rudy Project Cutline review – photochromic sunglasses for MTB trails

Previously I'd found that light-sensing lenses were too dark and too slow to clear for trail riding, but this ImpactX 2Laser Red photochromic lens works brilliantly

Rudy Project Cutline sunglasses with a ImpactX 2Laser Red photochromatic lens
(Image: © Rich Owen)

Bike Perfect Verdict

Even when fully darkened, the Cutline's red lens tint doesn't hinder riding in shaded trail conditions. The lens itself is extremely hardy too and fogging has rarely been an issue. Overall, these are the best photochromic sunglasses for MTB we've ever tested.


  • +

    Ideal for all but the most dimly lit riding conditions

  • +

    Hardy lens remains scratch-free after months of use

  • +

    Excellent lens quality and resists fogging very well

  • +

    Individual frame parts can be removed as required

  • +

    Comes with hard and soft case


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    Premium price

  • -

    Lens doesn't go completely clear

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I'd never been a fan of photochromic lensed sunglasses for mountain biking. While they're quick to darken, every lens I'd tried was too slow to clear once I'd entered a dimly-lit area such as the woods. The Rudy Project Cutline glasses with its ImpactX 2Laser Red lens changed all that though and are definitely one of the best mountain bike sunglasses I've ever tested.

Rudy Project Cutline sunglasses with the lower lens pieces removed

You can turn the full frames into half-frame or frameless glasses if you wish (Image credit: Rich Owen)

Design and specifications

Rudy Project's Cutline sunglasses come in a wide range of frame and lens options. I've been testing the Matte Black frames with the ImpactX 2Black lens ImpactX along with a 2Laser Red lens – available separately.

The semi-flexible lenses are said to be unbreakable "for life", though the warranty is for two years. ImpactX lenses are made using "patented polyurethane optical polymers" which Rudy Project says results in a lens that's lighter than polycarbonate and plastic alternatives. The lenses are also treated with a number of different anti-reflective and hydrophobic layers and coatings, they're also vented with four slots in the upper part of each lens.

The frames are a mixture of stiff (arms and hinges) and flexible (everywhere else) rubberized plastic. The nose piece can be adjusted to suit, and the total weight for the glasses is an average 36g. If you want to lighten the load on your face or change your look, you can convert the full-frames to half-frame or barely any frame, as the top and two bottom sections can be removed individually. You can also customize your glasses by buying a frame kit of a different color and swapping out the interchangeable parts.

There's plenty of flex in the glasses and the arms point slightly inwards to softly grip the slides of your head, while the tips of the arms turn slightly outward.

Rudy Project Cutline sunglasses with an additional lens

The photochromic 2Laser Red lens is excellent for all but the darkest light conditions (Image credit: Rich Owen)


I've been testing the Cutline glasses for many months in a wide range of riding and light conditions and have been seriously impressed. The glasses feel secure yet light and comfortable, and have worked well with every helmet I've tried them with. Lens quality is top notch and the glasses are big enough so as not to impair your vision in any way.

The supplied 2Black lens works well in open riding conditions. However, like every photochromic model I've tried, it's too slow to return to clear when entering darker sections of trail – which forces you to drop your pace for the four minutes or so that the lens takes to react to the dimmer light.

Switching to the additional 2Laser Red lens (sold separately but also available with different frames) made a huge difference though. Red lenses work well in shady woodland conditions, so the time it takes for the lens to lose its tint has never been an issue even when plunging from full sun to forest darkness.

I've been really impressed with how tough the ImpactX lens is too. The Cutlines have been regularly splattered with winter filth, stuffed into packs and pockets while already dirty and without their soft case, but remain scratch and mark-free after many months of riding.

Almost as impressive is how resistant they are to fogging. I've had zero issues with them at lower temperatures, but have had occasional mild fogging when working hard on slow climbs during hot days. The lens clears as soon as more air moves past them though and I've yet to ride in a pair of glasses that never fog up at some point.

Rudy Project Cutline sunglasses seen from above

The glasses arms grip your head but without causing any discomfort even when wearing for hours (Image credit: Rich Owen)


Rudy Project's Cutline glasses with an ImpactX 2Laser Red photochromic lens are an excellent option for almost all light conditions. In fact, the only time I've taken them off to see more clearly has been in wooded trails when riding after dark – as there is still a minuscule tint in the lens even at its clearest.

Scratch resistance on these glasses is second to none. The Cutlines have been properly mistreated but there's not a mark on the lens.

One very minor point is that you can't actually buy the Matte Black Cutline with the 2Laser Red lens I've tested here unless you shell out for an additional lens. However, it is available with the red/back Carbonium frame option and both models come with the same $269.99 / £219.99 / €254.90 price tag.

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The lowdown: Rudy Project Cutline
Lens qualitySuperb clarity and resists fogging well★★★★★
DurabiltyLens and frames are extremely tough★★★★★
Light conditionsExcellent in all but the dimmest light★★★★
Value for moneyTop price but you get an excellent pair of glasses★★★★

Tech specs: Rudy Project Cutline sunglasses

  • Price: $269.99 / £219.99 / €254.90
  • Additional lens price: £99.99 
  • Lens type: ImpactX (photochromic)
  • Weight: 36g
  • Spares available: Lenses and frame kits
  • Rival products: 100% S3
Richard Owen
Editor, Bike Perfect

Rich is the editor of the team. He worked as a print journalist and editor for over 20 years, before transitioning to purely digital media in 2021. Rich bought his first mountain bike (a rigid Scott Tampico) in 1995 and has been riding MTB for almost 30 years. He likes hitting flowy yet technical trails and is a jack of many MTB trades, competing in cross-country, enduro and long-distance races over the years. A resident of North Devon, he can mostly be found pedaling furiously around his local trails, or slightly further afield on Exmoor and elsewhere in Britain's southwest.

Current rides: Merida One-Forty 6000, Banshee Paradox

Height: 175cm

Weight: 69kg