K&F Concept 46mm Variable ND Filter ND8-ND128 (3-7 Stop) HD Hydrophobic VND Filter for Camera Lens No X Cross

SKU: KF01.1446

I want to add another filter to stack on to my 82mm nd filter and was wondering what size thread i should use for the front.
Answer Question
Hi, if you wand add other filter on the front of this nd filter , it would be larger one size than this filter , the 82mm nd filter need 86mm lens cap or other filter, thanks