Celestron 72370 Outland X 10x50 Waterproof Monocular with Smartphone Adapter, Bluetooth Remote, Eyepiece Covers and Belt Case - Durable Housing, BaK-4 Prism Glass and Multi-Coated Optics, BlackA PORTABLE GRAB AND GO OUTDOOR SCOPE: Perfect for wildlife observation, sightseeing, hiking and sports events with its large 50mm objective lens and excellent light gathering capability COATINGS & PRISMS: BaK 4 prisms and multi coated optics provide improved contrast and resolution by increasing light transmission through the entire optical path INCLUDED ACCESSORIES: Carry with ease with the handy belt case, also includes a cleaning cloth, eyepiece