The H&Y ND4 Magnetic Filter is a professional neutral density filter designed for use with H&Y RevoRing systems in the diameter range of 67 to 82 mm. This filter reduces light transmission by 2 stops, allowing photographers and videographers to achieve creative long exposure effects in bright lighting conditions. Made from high-quality Schott glass with a 9-layer coating, the filter maintains optical clarity while minimizing reflections and preventing loss of sharpness. The magnetic attachment system ensures quick and secure mounting on compatible RevoRing combinations. A nanocoating provides water and dirt resistance, making it easier to clean with a microfiber cloth. Ideal for landscape, water, and long exposure photography, this filter enables creative effects such as smoothing flowing water or capturing cloud movements while maintaining sharpness in stationary elements. The filter is specifically designed for RevoRing systems with permanently installed filter units and is not compatible with basic RevoRing versions without integrated filter mechanisms. The high-quality construction from special glass with multi-layer coating guarantees lasting optical precision and reliable performance in professional applications. The magnetic adhesion allows for efficient work under time pressure without compromising stability. The dirt-repellent nanocoating protects the surface from damage and preserves optical properties over a long lifespan. For demanding photographers and videographers, this filter offers reliable light reduction while maintaining consistent image quality and expands creative possibilities in various shooting situations.