1. Extremely thin ring reduces the occurrenceof vignetting even with wide angle lenses. 2. Aircraft grade aluminum filter ring provides high strength, corrosion resistance, superior stability and critical filter alignment. 3. German manufactured Schott Glass B270 with exclusive multi-layer Anti-Reflective Coating for perfectly linear, uniform light reduction from edge-to-edge, reflection reduction and precise color rendition. 4. Protective Coating on both sides for easy cleaning and superior performance. 5. Lightweight, high performance scientific grade aluminum filter ring provides high strength, corrosion resistance, stability and critical filter alignment. 6. Available in ND8 (3 stops), ND64 (6 stops) or ND1000 (10 stops).