BSA CATSEYEBSA made the catseye as bright as they possibly could. They started with extra large objective lenses to gather in as much light as possible. Camera quality glass was used to give a clear, undistorted, flat image. The objective and ocular lenses were fully coated to provide the brightest view without glare and reflections. Then to brighten up the shadow areas they add, just a splash of amber tint. All catseye scopes are waterproof, fogproof, and shockproof, and come with a limited lifetime warranty. All Catseyes come with knurled speed focusing rings.