For NiSi S6 150mm Filter Holder, Aluminum Alloy Construction, 360° Rotating Gears, Designed for Sigma 14-24mm f/2.8 DG DN The NiSi S6 150mm Filter Holder Adapter Ring is designed to enable the use of a NiSi S6 150mm Filter Holder System on a Sigma 14-24mm f/2.8 DG DN Art (Sony E and Leica L) lens. The use of the S6 filter holder is easily accomplished by first sliding the adapter ring over the integrated hood of a lens and tightening. The adapter ring accommodates a NiSi S6 circular filter for NiSi S6 including a Circular Polarizer (CPL) and UV filter. When combined with the adapter ring a compatible polarizer filter can be rotated to adjust its effect. Both the external dials on the adapter ring allow for the independent rotation of the circular polarizer. A NiSi S5 150mm filter holder can then be placed over the adapter ring. After being fitted onto the adapter ring the filter holder's pull-and-release locking-pin helps to provide a reliable yet adjustable connection that allows the filter holder to be rotated 360? permitting the use of graduated neutral density and other filters that are enhanced by varied positioning. For durability this adapter ring features an aluminum alloy construction. The adapter allows very quick installation and removal without removing the lens from the camera.