100x180 Zoom Binoculars Day Night Vision Bak4 Prism High Power Waterproof with Case Magnification: 10-180x Objective Lens Diameter: 50mm (available in broadband green or blue coating) Eyepiece Diameter: 17mm Field of View: 235 ft/1000 yds; 78 m/1000 m Prism Type: Bak4 Waterproof: Nitrogen-purged lens barrel for waterproof and fogproof performance; resistant to moisture and daily damp conditions Construction: Metal lens barrel with rubber armor for durability, comfort, and secure grip; sleek design with fine craftsmanship Focusing System: Central focus knob with right-eye diopter adjustment for precise focusing Coating: Multi-layer green vacuum-coated lenses for high light transmission and clear, high-definition images Applications: Ideal for birdwatching, sports events, concerts, outdoor travel, and scenic viewing Care Instructions: Store in a dry place to prevent internal fogging or mold. Avoid exposure to prolonged moisture. If lens cleaning is required, use a cotton swab lightly dampened with alcohol or gasoline and gently wipe the surface. Do not use dry cloths or water, as they may scratch the lens coating. Note: These binoculars feature light-amplifying night vision technology and require some ambient light to function; they are not designed for use in complete darkness.