Skque&reg; 100 x 150mm ND4 Grad 0.6 Grey Neutral Density Filter High quality ND4 0.6 grad grey neutral desity filter. 0.6 density provides a 2 stop reduction in light in selective areas. ND filter is ideal for using larger apertures and/or slower shutter speeds in bright conditions. Neutral density filters do not affect the overall coloration of the image. ND filter provide a ideal way to dramatically improve your shots.