NRC X3.Earth glasses

The NRC X3.Earth sunglasses are lightweight and comfortable, they offer high clarity thanks to a Zeiss lens, and the frame is made largely from a plant-derived material that's dye-free, the idea being that you're doing your bit for the environment.

Let's start with that frame. NRC's X3 glasses are available in various models, this Earth variety coming with a frame that's made from UVM, or Unique Vegetal Material, which is said to have "a 65% natural origin". The remainder is nylon.

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UVM is slightly softer to the touch than the TR90 thermoplastic used for most eyewear, but on your face you'd never tell the difference. The X3.Earth glasses just feel normal.

The UVM is dye-free, making a frame that's translucent and not-quite-white. NRC describes the colour as 'milky white', which seems a reasonable description. You can just about see the screw used at the hinge through the UVM in certain lights.

The tips of the arms (or temples) are made from soft-touch Megol thermoplastic with a rubbery feel, and the same goes for the nosepiece which is width adjustable – you can bend the sides in or out slightly with your fingers to get the fit just right.

I also like the fact that there's no frame at the sides of the lens, or underneath it. As well as keeping the weight down, it means there's nothing to interrupt your vision. I find that especially valuable when making that quick check over the shoulder before turning.

You can't alter the shape of the arms but the distance between the tips is under 10cm when unworn, meaning that the glasses are under slight tension when you put them on, the inherent springiness of the material helping to holding them in place without so much pressure as to cause discomfort. Some glasses are prone to slipping when you get sweaty, but these have stayed in place reliably during three months of regular use, even on the hottest summer rides.

You get a high-quality Zeiss lens called Super Nylens 2.0 Greenwood Gradiant. It has "a forest green colour gradient [that] naturally diffuses blue light, boosting contrast and brightness in the lower section to guarantee optimum visual safety in any conditions", according to NRC.

There's certainly a green tinge to the lens, but I asked a couple of other people to try these glasses and they didn't pick up on that, describing the lens as 'smoky' or 'grey'. I'd say that it mildly increases contrast while reducing glare and harsh sunlight.

The lens isn't as large as some you see these days, but it offers a decent amount of coverage, particularly because it wraps around the sides of your face. There are models in NRC's range that extend further down, if that's what you're after.

The top of the lens is considerably darker than the bottom, helping to block out bright light from overhead without affecting your view of the road to the same degree. If you want the figures, light transmittance at the top is 9.5%, in the centre it's 15%, and at the bottom it's 24%. It's a personal preference but I quite like the gradient. If it's not for you, the X3 is available with other lenses – such as Zeiss Super Nylens 2.0 Amazon Green Mirror that gives a 20% light transmittance in all areas – although the X3.Earth comes only with the Greenwood Gradiant.

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The lens features anti-fog holes above the nose bridge and out by the hinges although, as with any other glasses, you can still get them misted up with vapour if you're sweating hard and airflow is low – when you're climbing a steep hill, for example. Still, the X3.Earth glasses are pretty good in this respect.

If you want more ventilation you can also pop out the small tabs on the temples – the black rubbery areas with the white NRC logos – although I can't say that I could discern any difference in performance either way. Those tabs won't come out accidentally, ridges at their edges meaning they're held in place securely.

The lens is shatterproof and has a hydrophobic coating called Ri-Pel that's designed to repel water and oil – although get your grubby little fingers over it and you're going to leave a smudge. It also has an anti-scratch coating. A quick inspection shows that after a lot of use and abuse over the past few weeks, the lens is still in near-perfect condition, which bodes well for long-term durability.

You get just one lens with the X3.Earth sunglasses but you can buy extra nylon lenses, priced from €90. Swapping them over is easy without the need for any intricate design features. There's enough flex in the frame to allow you to pop the lenses in and out without any fear that you're going to snap something.

You can also get a transparent nylon optical clip for the X3s (€24/£22) that allows you to fit prescription lenses to the nosepiece. 

These are pricey for glasses with a single lens, albeit a very good one. NRC's own P-Ride.Skyrun glasses that we reviewed earlier in the year are £112, for example, and Oakley's EVZero Blades are £143. You can, of course, find much cheaper eyewear too.

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Standard NRC X3 glasses – of the non-Earth variety – start at €175 (around £158), so you're paying extra for the UVM. If the material is important to you, it's also used for NRC's X1 and X2 glasses, but they're also priced €215 (£194).

Conclusion

The NRC X3.Earth glasses are lightweight and comfortable, with a frame material that's largely derived from plants. You also get excellent optics courtesy of Zeiss and the ability to add a prescription lens. The price is steep, though.

Verdict

Comfortable eyewear with a very good lens and a frame that's largely derived from plants