When your prescription specifies single vision lenses, it means you are either farsighted or nearsighted. If single-vision is your prescription, youæll want lenses that work for your particular lifestyle. Bobster offers transitional lenses for indoor and outdoor activities. The lens lightens to a clear indoors and at night while it darkens to a smoke grey during the day in sunlight. Please visit bobster.Com if you have any ordering questions or need information.