They are smaller than advertised. Will not fit properly on glasses.  Also arrived DIRTY.  NOTE; THIS PRODUCT CAN NOT BE RETURNED.  Lenses are actually 58 mm x 40 mm.  Also the shape of the clip-on makes it very difficult to attach properly to glasses.  The vendor besgoods must know that these lenses are smaller then advertised.  Also no where in the advertisement does it say that this item can not be returned.