Celestron skymaster binocular 25x70 large aperture binoculars are phenomenal value for high performance binoculars and are ideal for astronomical viewing or for terrestrial land use especially over long distances each pair of celestron skymaster binoculars feature high quality bak 4 prisms and multi coated optics for enhanced contrast clear sharp views and ultra sharp focus across the field of view celestron has designed and engineered the larger skymaster models to meet the special de