Apochromatic Lens System:The apochromatic lens system gives you the result of images that have greater contrast, sharpness, and color definition/UHD Glass: Extra-Low Dispersion glass gives you an image with little or no chromatic fringe so the final result brings the ultimate clearest and sharpest image to your eyesESP Dielectric Coating:ESP Dielectric Coating is a multi-layer prism coating that reflects over 99% of the light to your eyes bringing you a clear, bright image that displays accurate color reproduction.Magnesium Chassis:Magnesium chassis give you the strength of a metal chassis while reducing the weight as much as 30%XPL Coating:XPL Coating gives you extra protection on the exterior lenses from dirt, oil, and scratchesBak4 Prism:Bak-4 glass prisms reflect more light to your eyes which will give you a brighter and sharper image.Advanced Fully Multi-Coated:Advanced Fully Multi-Coated lenses give you better light transmission to bring optimum brightness and true color across the entire light spectrum.Argon Purged: Argon Purging uses the inertia gas with bigger size molecules to purge any moisture out of the tube giving you better waterproofing and thermal stability.Waterproof:Waterproof to protect the binoculars in the harshest weather conditions or if accidentally submerged underwaterRotating Ring:Rotating Ring allows you to rotate the scope around the tripod supporting ring into the most comfortable and convenient angle for observationSpecifications:- Magnification: 20-60x- Objective Lens Diameter: 85 mm- Prism Glass: Bak 4- Apochromatic Lens System: Yes- ESP Dielectric Coating: Yes- XPL Coating: Yes- ED Glass: Yes- Lens Coating: Advanced Fully Multi-Coated- Field of View: 99-47 ft- Eye Relief: 0.77-0.7"- Close Focus: 39.4- Dimension (L x W): 16.9"X4"- Weight: 70 oz