Firecrest ND 77mm Graduated Neutral Density 0.9 (3 Stops) Filter for photo, video, broadcast and cinema production Firecrest technology is neutral across the whole spectrum, including UV, visible and infra red 77mm diameter stackable filter reduces light by 3 F-stops across the top half of the filter Firecrest multicoating technology makes the filter hydrophobic and scratch resistant For use in landscape and horizon shots Manufactured in the UK using Schott Superwite glass, the finest optical glass available