Ideal for amateur astronomers, the SkyMaster Pro binoculars from Celestron have large 80mm objective lenses that are ideal for observation at dusk, dawn, and night-time. They are both waterproof and nitrogen-purged, making them suitable for use in all and any weather conditions, and are rubber-armoured to protect from knocks and scratches. Built into the binoculars are a tripod adapter and RSR rail for attaching a red dot finderscope. With each surface multi-coated with Celestron's proprietary XLT coating technology, and BaK-4 prisms within the binoculars, the Celestron SkyMaster Pro 20x80 Binoculars will produce crisp, high contrast images with outstanding resolution.