Firecrest ND 165x165mm (6.5"x6.5") Neutral Density 0.9 (3 Stops) filter for Lucroit 165mm holder 165mm filter reduces light by 3 F-stops Firecrest technology is neutral across the whole spectrum, including UV, visible and infra red Firecrest coating is sandwiched within filter, providing protection against scratching and damage Made in the UK using Schott Superwite glass, the finest optical glass available Compatible with all 67mm holders, so a single filter can be used on multiple lenses