Bought to have on hand a good pair of extra glasses with my laptop. I work a lot and force, the view takes a hit (tingling, even pain ...) to preserve capital! They are not expensive in relation to the services rendered: the filter effect is excellent and no image distortion. The selected frame is not solid but more aesthetic. I usually take steel frames but they often twist, the optician free straightens the corner with great kindness but it does not always and everywhere a real troubleshooting does no harm. They are used quite often. The correction is excellent and no headaches.