B+W 37mm ND 0.9-8X Neutral Density Filter with Multi-Resistant Coating (103M) 0.9 ND filter darkens the image, allowing you to photograph with a longer shutter speed or wider aperture than normally required. Providing a 3 stop exposure reduction, this filter allows you to control depth of field and convey movement more easily. Filter does not affect coloration of the image. Constructed from high quality Schott glass for optical clarity. Brass filter ring helps to prevent jamming and provides additional strength. Plastic case included for storage and transport. Multi-Resistant Coating offers both protection to the glass and helps to improve light transmission and image quality.