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Amazon.com : ICE ND1000 Filter for Cokin P Neutral Density 10 Stop Optical Glass 84mm x 98mm : Camera & Photo
Amazon.com : Cokin Square Filter Full ND Creative Kit - Includes ND2 (1-Stop), ND4 (2-Stop), ND8 (3-Stop) for L (Z) Series Holder - 100mm X 100mm : Camera & Photo
Cokin 67mm NUANCES Variable ND Filter (5 to 10-Stop) CNV32-67
Amazon.com : 24 PCS Square Filter Kit ND Filters Graduated Full Color Lens Filter Set for Cokin P Series with Adapter Rings(49-82mm) Filter Holder Lens Cleaning Pen and Other Accessories for DSLR
Amazon.com : Cokin Square Filter Full ND Creative Kit - Includes ND2 (1-Stop), ND4 (2-Stop), ND8 (3-Stop) for L (Z) Series Holder - 100mm X 100mm : Camera & Photo
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Amazon.com : Hoya 77mm Variable Density Screw-in Filter : Camera Lens Neutral Density Filters : Camera & Photo
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Amazon.com : Cokin Square Filter Gradual ND Creative Kit Plus - Includes M (P) Series Filter Holder, Gnd 1-Stop (121L), Gnd 2-Stop (121M), Gnd 3-Stop Soft (121S) : Camera & Photo