Vortex Optics Viper HD Roof Prism Binoculars The Viper HD binoculars have an advanced, high density optical system with enhanced, anti-reflective lens coating for stunning image quality and top tier light transmission Dielectric, multi-layer prism coatings provide bright, clear, color-accurate images. Coating on roof prism models enhances resolution and contrast A compact, rubber-armored chasis and armortek coating ensures the Viper HD is ready for any hunt Adjust the multi-position eyecups to optimize fit for comfortable viewing with or without glasses. A locking right eye diopter adjusts for focal differences between your eyes Argon purged and o-ring sealed, the Viper HD defies the elements ensuring waterproof and fogproof performance, no matter the conditions