Heliopan 72mm ND 0.6 - 4x Neutral Density Filter
Neutral Density filters evenly reduce the amount of light passing thru the lens without effecting color. Ideal for reducing bright light in large aperture situations when a narrow depth is field is needed. Allows for slower shutter speeds when blurring or showing of movement is desired. Allows balancing of exposure to highlight a key subject. Lets you use higher speed films in bright light.