Celestron’s SkyMaster 20x80 binocular is a phenomenal value for high performance. Ideal for astronomical viewing or for terrestrial (land) use, especially over long distances. The giant 80 mm objective lens offers maximum image brightness in low-light and long-range conditions. This model features high quality BaK-4 prisms and multi-coated optics for sharp, clear views. Celestron has designed and engineered the SkyMaster binoculars to meet the special demands of extended astronomical or terrestrial viewing sessions.