40.5mm Variable ND Filters ND2-32 Adjustable Fader Neutral Density ND2 - ND32 Filter, NO Spot X Black X Issue, MRC 28-Layer, Ultra Slim, Waterproof

SKU: KF01.1163

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it depends on if your polarized filter has threads on both sides if so yes. if not no. This ND filter does not have threads on the outside, therefore you can't stack another filter on top of it. 
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Yes, the nd filter could stop at the end of the ranges. 
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Yes, the nd filter could stop at the end of the ranges.