XCSOURCE Variable Adjustable Neutral Density ND Fader Filter ND2 ND4 ND16 to ND400 With Case 55mm LF303 New 55mm Slim Adjustable ND Filter - ND2 to ND400 Works with any lens with a 55mm filter thread; manual or autofocus, digital or film.. ND filters (Neutral Density) reduce the amount of light reaching the film without affecting the color. Enable slower shutter speeds and wider aperture for effectively decreasing depth of field. Great for portraiture and outdoor scenes. Back thread diameter (attach to lens, male thread): 55mm