The Vanguard Endeavor RS rifle scopes superb image quality is delivered through multilayer anti-reflective coatings for increased light transmission and optical designs using premium HOYA ED glass. Featuring large fields of view, a rapid focus eyepiece and enhanced contrast combine to deliver a positive experience afield. The single-piece 1" tube is constructed from aluminum. Its hard, anti-scratch, anodized matte surface delivers a robust and ergonomic platform. The Endeavor RS is sealed against dust and moisture, nitrogen-purged and recoil-resistant to provide a lifetime of dependability and success. Precise windage and elevation adjustments offer reset capability and accuracy with a locking side parallax system on certain models.