This adjustable ND3-ND400 filter features two stacked polarizers, allowing for seamless light reduction from 1.5 to 9 stops. This means you can capture stunning images with high-aperture lenses without worrying about glare in bright sunlight, or achieve a beautifully long exposure to soften moving water. Crafted from high-quality optical glass by Hoya, this filter ensures clarity and precision in your photography.