Copper is a high light transmitting lens making it an excellent sight-fishing lens. The light that comes through the lens delivers the detail needed to discern the difference between the bottom structure and fish. Copper lenses are also good in areas with muddy water where the lens is excellent at reducing glare and providing a spotlight on movement in dirty water. There is no equal if you are looking for a lens that enhances your vision in all conditions. This lens is suitable in all variable light conditions. It is also an excellent driving lens.