Vortex 10x42 Viper HD Binoculars (2018 Edition). This updated version of the Vortex Viper HD 10x42 binoculars features a wider field of view and longer eye relief for more spacious and comfortable viewing. Optically, the binoculars use proprietary XR anti-reflection fully multi-coated optics to maximize light transmission and improve contrast and color fidelity. The compact roof prisms are dielectric coated, and phase-corrected coatings reduce internal interference and light loss, delivering bright, sharp, high-contrast images with accurate color. The 42mm objective lenses enhance light-gathering for clear views in low-light conditions such as dawn, dusk, or dense brush. The chassis is lightweight, impact-resistant polycarbonate, temperature-stable, and rubber-armored for a secure grip. The binoculars are O-ring sealed and argon-filled for waterproof and fog-resistant performance. Features include a closed bridge design, large slip-resistant focus knob, locking right-eye diopter, 56-75mm interpupillary distance, twist-up click-stop rubber eyecups, tripod mountable with optional adapter, 17mm eye relief, and 4.2mm exit pupil. ArmorTek coatings protect lenses from scratches, oils, and debris. Package includes Vortex 10x42 Viper HD Binoculars, Vortex GlassPak binocular harness (tan), neck strap, rainguard eyepiece cover, 2 tethered objective lens covers, limited lifetime warranty, MPN: DB-218, UPC: 875874007420.