Variable Neutral-Density, 82mm
Amazon
NiSi 82mm Swift Add-On Kit for NiSi True Color VND 4 Stop Neutral Density to Create 5-9 Stop VND, Along with 1/4 Density Black Mist Photography and Videography
Adorama
NiSi Swift Add On Kit w/ND16 4 Stop & Black Mist 1/4 Filter for 82mm Swift VND