Celestrons SkyMaster Series of large aperture binoculars are a phenomenal value for high performance binoculars ideal for astronomical viewing or for terrestrial (land) use - especially over long distances. Each SkyMaster model features high quality BaK-4 prisms and multi-coated optics for enhanced contrast. Celestron has designed and engineered the larger SkyMaster models to meet the special demands of extended astronomical or terrestrial viewing sessions.. For maximum stability and secure optical alignment the 70mm SkyMaster model features enhanced structural reinforcement to the main binocular body. As an additional convenience, the 70mm SkyMaster model also includes an integral super rigid photo tripod adapter. The SkyMaster Series binoculars are built to provide years of magnificent views of the world around you and the heavens above.