This Firecrest Ultra Long Exposure Kit includes 3, 6, and 10 stop ND filters. This combination is extremely versatile, allowing the shooter to use 3, 6, 9, and 10 stops of ND, plus the magical 13 and 16 stops for true long exposure shots of 5 minutes and longer. This kit is offered in two versions, Circular Firecrest filters and 100mm Firecrest ND with holder and adapter rings.