The E39 UVa II Filter is a general-use, clear filter designed to absorb ultraviolet light and reduce the bluish cast of daylight without introducing additional coloration or contrast, requiring exposure adjustments, or causing internal ghosting and reflections due to its multiple layers of anti-reflection coatings, and it is constructed from optical glass for clarity and color fidelity with a black aluminum-alloy filter ring for durability and lightness, designed to mount onto a lens with 39mm front filter threads, serving as a general protective filter that helps reduce dust and moisture on the front lens element while providing additional protection against drops and scratches.