Built for epic adventures in harsh environments, the BX-5 Santiam HD binoculars dominate other optics in their class. Their generous eyebox is designed for long glassing sessions with no eye-strain. The open-bridge design is comfortable and easy to carry, while the advanced prisms and Twilight Max HD Light Management System ramp up light transmission and redefine low-light performance; helping you see more in less light. And, of course, their glare management, clarity, and resolution are second to none. Features: Abbe-Koenig prism - maximizes light transmission, clarity, and resolution at extended ranges BAK 4 prisms - delivers a perfectly round exit pupil with virtually no edge distortion and a crisp, clear image Diopter focus Ergonomic design Fully multi-coated lens system High-definition, calcium-fluoride lenses ensure incredible clarity at all magnification levels Phase coated roof prisms significantly increase resolution for a sharp sight picture from edge-to-edge of the visual field Made with Leupold's Proprietary nitrogen sealing process, which has become the industry standard Rugged and absolutely waterproof A built-in 1/4-20 rotatable tripod adapter port makes it easy to mount to a tripod Twist-up eyecups and long eye relief Advanced HD lens system DiamondCoat 2 Sheds dirt and water for clear, crisp images with the Guard-ion lens coating Twilight Max HD light management system Absolute waterproof and fogproof integrity means it's ready to perform in the field, in all conditions