Formatt Hitech 100mm Landscape Filter Kit Colby Brown Signature Edition (for 77mm Lens Thread) Contains 3 different styles of the popular ND filters in addition to a 77mm adapter 100mm Aluminum holder is ideal for stacking up to 3 filters Includes an exclusive technique booklet authored by Colby Available in three sizes 67mm, 85mm and 100mm Made in the UK on the most advanced computer-controlled manufacturing equipment in the industry