Hawke Frontier ED X Full-Size Binocular - 8x42 - High performance lens coatings and Dielectric Coated prisms ensure the highest level of light transmission. ED X models benefit from Extra-low Dispersion glass for controlled chromatic aberration and the elimination of color fringing. Features Extra-Low Dispersion (ED) Glass Dielectric Coatings High Resolution Phase Corrected BAK-4 Roof Prisms Water Repellent Lens Coatings Magnesium Alloy Chassis Focus From 2m Replaceable Twist-Up Eye Cups With Position Stops Stay-On Lens Covers Nitrogen purged. Waterproof. Fog proof. Hawke No-Fault Lifetime Warranty.