High-quality 100x150mm Reverse-Graduated ND 0.9 Filter (3 Stops) for precise exposure control Designed specifically for capturing balanced sunrise and sunset photography Features a stronger density in the center with a gradual transition zone for natural, balanced exposure Ideal for use with lenses of 24mm or wider on a full frame DSLR (or equivalent) Hand-manufactured by skilled technicians at Lee Filters' Andover factory for unmatched precision and quality Easy to position in the holder for optimal exposure control at the horizon line