A cover for use in connection with a mirror of a vehicle is provided. The cover is provided with a lens having an electrically activatable material. The lens is positioned in front of the vehicle mirror. The electrically activatable material blocks visible light directed towards the vehicle mirror such that the electrically activatable material prevents the visible light from being reflected off of the vehicle mirror when the electrically activatable material is set to a light inhibiting state. A device that holds the lens is securable to the vehicle mirror. The electrically activatable material of the lens is configured to be switched to the light inhibiting state in response to user operation such that the lens prevents reflection of the visible light off of the vehicle mirror to reduce observability of the vehicle mirror.