The Kase Light Pollution Filter (Neutral Night 7 Astro filter) is a light pollution filter, which is used to reduce your influence of artificial light at night shots. As with all Kase filtering the Wolverine series to expect a high-quality Pro-glass filter which is shutterproof and easy to clean. This filter is a disc filter. Product information Kase Neutral Night Astro Filter: reduces artificial lightsizes: 77mm and 82mmshockproofscratch resistantThis filter is NOT magnetic but is mounted via screw thread.You can also use the filter on lenses with a smaller lens diameter. For this you need a suitable step up adapter ring.You can find this adapter ring here.