The Vanquish Binocular by Vortex Optics is a compact performer that comes courtesy of Vortex's forward-thinking engineering and on-the-go tactics. The reverse porro prism design uses high quality glass and fully multi-coated optics to render images crisp and bright with a wide field of view. Optics are sealed with O-rings to prevent moisture, dust, and debris from getting inside the binocular. Nitrogen gas purging delivers fogproof, waterproof performance. Rubber armor provides a secure, non-slip grip and durable external protection. Adjustable eyecups twist up and down for comfortable viewing with or without eyeglasses. Right eye diopter in right eyepiece adjusts for differences in a user's eyes.