Bushnell spotting scopes give the advantage from the worlds high point of brightness, clarity and edge-to-edge detail - whether youre birding at sea level or hunting above timberline. The HDOS (High definition optical system) combines Bushnell key technologies: ED Prime Extra-Low Dispersion glass, premium BaK-4 prisms and fully multi-coated lenses. Together these deliver flawless color fidelity, ultra-crisp images and optimum light transmission.Features : Twist-Up Eye Cups Air Tight Straight Eyepiece Waterproof