The Viper HD - a premium-quality binocular packed with everything you need and nothing you don't. Rugged, compact and lightweight (one of the lightest full-size binoculars to date), it's easy to see why the Vipers are award winners. Add in HD (High Density) extra-low dispersion glass for impressive resolution and color fidelity and the Vipers change more than the game. They change the results, too.