Pushing the limits of optical performance, Vortex Razor HD Binoculars are small, light, bright, and strong. These binoculars come packed with exclusive features to ensure maximum optical performance. These features include an apochromatic optical system, HD extra-low dispersion glass, XRPlus fully multi-coated lenses, and a roof prism design with dielectric prism coatings - all of which gives the Razor HD and Razor UHD Binoculars excellent light transmission, a clearer image, and edge-to-edge clarity. The pristine optical quality is perfectly matched with a solid construction composed of a true open hinge design, an argon gas purging with o-ring seals to prevent fogging, and a magnesium chassis to shrug-off minor shocks and impacts.