In the world of sports sunglasses, you’d think there’d be nothing new under the sun. Shades are shades, right? We thought so until we tried React’s solar-powered, light-adaptive shades. Battery-free, hassle-free and pleasingly light, React Optray sunglasses turn infrared light into electrical impulses to automatically toggle between medium, dark and very dark states as the conditions require.

From riding into a tunnel, out into the sun, out from under the trees into open terrain, React Optray sunglasses instantly adapt to the light so you can see more of what matters. They're so fast and seamless to switch tints that the Swiss brand's ambassador, über-fast Stefan Küng, credits them with keeping him more relaxed on the road, better prepared for what's around the corner, and faster to make the decisive move when the chips are down.

We've been testing the React Optray sunglasses since the team behind the brand popped by the shop to say hi, and we have fallen in love with how well they work.

It's uncanny to have your eyewear change tints in response to the conditions, even more so when you don't notice the shift. After a day of wearing React, your eyes relax, as your brain realizes it doesn't have to adapt to every little change of light anymore. Instead, a solar cell-powered chip turns observed infrared into electrical impulses, which are infused into the rear LCD panel, shifting tints as conditions demand. That process takes a blazing 0.1 seconds - so fast your eye can't register it.

React is an branch of Optrel Sports, maker of some of the world's finest welding helmets, goggles and systems. The brand came to pass about nine years ago as a commercialization of some of the welding arm's more esoteric technology.

The team tasked with bringing Optrel's infra-red-reading, solar-powered sunglasses to market spent several years developing the tech, securing patents and a lot of testing miles along the way. And the best part is, the sunglasses are handmade in cowbell country, not just 'designed' there. And we mean Switzerland, just in case you've never ascended past a herd of gently clanking herbivores en route to a summit fondue in that fair country and do not know of what we speak.