a visor having a curved transparent plate includes a photochromic material layer detachably mounted on the transparent plate . the photochromic material layer including a photochromic pigment is provided at the convex outer side of the transparent plate and a seal element is provided at a location to maintain a certain spacing between the transparent plate and the photochromic material layer and to prevent water ingress between the two surfaces . an anti - scratch coating is applied at an outer side of the photochromic material layer .