Darkens entire image, allowing you to photograph with a wider aperture or slower shutter speed than normally required, suitable to record movement/image blur in subjects such as waterfalls, streams, waves, clouds or any fast moving subject | Eliminates buying many fixed ND Filters as it is designed with a built-in rotating ring that controls neutral density ranging from ND2 to ND2000 (1 to 11 f-stop). The heavier the density, the slower your shutter speed will be | When using this variable ND filter at high ND values (9 f-stop or above) on wide angle lenses, it would appear "X" cross mark, vignetting, reflections or blur in the picture, this is unavoidable according to the structure and operating principle of a variable ND filter. If this is not acceptable to you, please go for a non variable ND filter, for example, a popular fixed ND1000 10 f-stop ND filter | The filter is constructed from optical glass that features 9 layers of anti-reflection coatings on each side(total 18 layers), making the filter anti-scratch, anti-static, oil and water-resistant | Compatible with all 82mm camera lenses. Your lens thread size will be printed underneath your lens cap or written somewhere on the lens barrel. Make sure you order the correct size otherwise it will not fit your lens