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Formatt Hitech Limited HT85ND1.8 85x85MM (3.35-InchX3.35-Inch) Neutral Density 1.8 (6 Stops)

Product Description :
Hitech filters are made from the highest quality 15mm optical resin
the filter is also available in 100mm 150mm and 165mm sizes
the 85mm size is useable with Hitech 85mm holder systems or any 85mm 335-InchSize holder