This is a Yuenu Original Einth Super Protect filter for classic lenses with limited thinness (0.05 inch (1.2 mm) thickness. Uses glass made by SCHOTT, a world-renowned glass manufacturer, and has been treated to be water-repellent/oil resistant coatings and an imitation process on the outer perimeter of the lens to reduce reflectivity of less than 0.3%. The design is made with a classic shape that is old fashioned.