Serengeti NuvolaMetallic Black /Polar PhD 555nm BlueLensesSerengeti Nuvola boasts cutting edge design and premium technology. Nuvola's rimless construction doesn't box in your view either. And these rimless lenses are connected with sleek but strong hinge-work for a distinctive look.Made from Grilamid TR90, Nuvola is lightweight for a comfortable fit. It's incredibly durable too. Megol temple tips and nose pads hold these snugly yet firmly in position. And it fits to the contours of heads.This one features new Polarised 555nm blue lenses. They enhance greens and yellows for the clearest views. Contrast is amazingly sharp too.Spectral Control fine tunes light transmission. Now colours are vibrant and the view is sharp. Plus Spectral Control also helps block most blue light (this type of light usually damages eyes and causes eye fatigue).Serengeti lenses are photochromic too. So they lighten and darken with the conditions (even inside the car where UV is minimal). Polarisation beats blinding glare – so there's no need to squint. UV400 lenses. Serengeti sunglasses come with a one year manufacturer's warranty.