The 67mm ND16 QuartzLine Solid Neutral Density 1.2 Filter from PolarPro is an ND filter with a 16x filter factor that provides a 4-stop exposure reduction. Its 1.2 density creates a darkening of the entire image, allowing you to photograph with a wider aperture or slower shutter speed than normally required. By slowing your exposure time or increasing your aperture, you can control depth of field and convey movement more easily. Neutral density filters do not affect the coloration of the image and are ideal for pairing with other filters. This filter is constructed from quartz glass for enhanced durability. To prevent internal ghosting and reflections, 16 layers of anti-reflection coatings offer scratch protection to the filter substrate while promoting clarity and color fidelity. The coatings associated with the PolarPro 67mm ND16 QuartzLine Solid Neutral Density 1.2 Filter also result in an improved beading effect when in contact with water or oil, allowing for more efficient cleaning. The quartz glass is set within a brass filter ring with side knurlings. Together, the brass material and knurlings prevent jamming and provide additional strength, as well as a textured grip when mounting or removing this filter from a lens.