Swarovski ATX/STX 85mm Modular Objective Lens High-density (HD) Glass: Enhances resolution, color and contrast Fully Multi-coated Lenses: Increase light transmission with multiple anti-reflective coatings on all air-to-glass surfaces Helical Focus Ring: Allows for quick adjustments Magnesium Body is sturdy and resistant to corrosion Rubber Armoring provides a secure, non-slip grip