1. Fully coated optical lens, ensures superior light transmission and brightness, helping you see almost any target, whether you're looking for birds or trying to get a better view of it. 2. See things closer to 16X and clearer and brighter with the 52MM objective lens and 18.5mm eyepiece lens. The larger the objective, the more light that enters the binocular, the brighter the image. 3. BAK4 prism, no black bars Clear image, leaves super clear and images. 4. Waterproof and anti-fog, the mirror is filled with high purity nitrogen, can be used on a rainy day and in a humid environment.