the marumi magnetic gradual grey filter reverse gnd4 (100x150mm) is a rectangular filter which allows you to capture a continuously changing landscape beautifully and easily. the marumi reverse gnd4 (graduated neutral density) is specially designed for use with the marumi magnetic filter holder m100, which is available separately (see optional accessories). due to the magnetic frame you attach the filter safely and quickly to the filter holder. the darkest part is in the middle of the filter glass, with the glass being increasingly transparent towards the upper side. this makes the marumi reverse gnd4 extremely suitable for photographing sunrises and sunsets. furthermore, the filter glass contains a multicoating (schott b270 glass), making it anti-scratch and water-repellent on both sides. this prevents for example fingerprints on the glass. the anti-static property of the filter glass also prevents sticking of dust particles and dirt. usage marumi magnetic gradual grey filter reverse gnd4 the rectangular glass of the marumi reverse gnd4 contains a metal frame on the sides, with a wide grip at the top and wavy edges at the side. this makes the filter easy to hold. due to the magnetic grip you attach the filter to the holder easily, so you can use the filter instantly. the holder then grabs the filter firmly, so that no vignetting occurs. you can stack a total of three filters to the filter holder m100, which can be easily adjusted in height by the magnetic strip.