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 HSM Art (Canon EF and Nikon F) 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.
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