Firecrest ND 77mm Neutral density ND 4.8 (16 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 16 F-stops Firecrest multicoating technology makes the filter hydrophobic and scratch resistant Firecrest performs perfectly linearly in the visible light spectrum, before completely eliminating the infrared energy at around the 700nm mark. Manufactured in the UK using Schott Superwite glass, the finest optical glass available Specialised ultra high density filter designed for long exposure photography