This kit contains all you need to get started with filters for your Nikon 14-24 ultra Wide Angle Lens. The kit includes the Formatt Hitech Lucroit 165mm Wide Angle Holder, and adapter ring for the 14-24, and a 165x200mm (6.5 x 7.87 Inches) 0.6 (2 Stop) soft edge graduated neutral density filters. Other filters can be purchased separately from the Formatt Hitech 165mm range. There are a number of Wide Angle Lenses where it is not possible to fit standard filters or holders because the way the barrel of the Lens is configured. Prominent amongst these is the Nikon 14-24 but there are many others including the Canon 4L and the Sigma 8-16 and 12-24. The Formatt Hitech Lucroit holder was designed by a Spanish Engineer (who was also a photographer) who wanted to find a solution to both the Nikon 14-24 problem and that of other similar Wide Angle Lenses. The holder fits on the Lens by a bayonet mount with a retaining rubber ring which holds it in place. It is designed to take a completely new range of 165mm (6.5 Inch) standard filters with grads in 165 x 200 (6.5 x 8 Inch). This means that, unlike other systems, it will not vignette on these Wide Angle Lenses. As it is also available with adapters for standard 72-82mm lenses it now comprises a total high end system for the pro user.