The 6 to 9-stop, 67mm Variable ND Filter from Kolari Vision rotates to cut 6 to 9 stops of light from entering your lens in bright outdoor environments. It darkens the image accordingly, allowing you to use slow shutter speeds and longer exposures, and to achieve cinematic motion blur. The filter features two pieces of premium glass. When you rotate the filter, the two pieces adjust and you can dial in the desired ND factor. The glass is multicoated, and the filter ring is aluminum and threaded on both sides.