Amazon.com : Polaroid Optics 67mm Multi-Coated Neutral Density Fader Filter – Variable Range ND2-ND2000– Holds Optical Quality – Compatible w/ All 37mm DSLR Cameras : Camera Lens Neutral Density Filters : Electronics
Nanopro Interchangeable Magnetic Variable Nd Filter Nd2-5/nd6-10 Neutral Density Optical Glass For 58 62 67 72 77 82 Camera Lens - Camera Filters - AliExpress
First try at the ND6 filter | This is one of the first shots… | Flickr
Tiffen 82mm Water White Glass NATural IRND 0.6 Filter (2-Stop)
Polaroid Optics 40.5mm Neutral Density Filter [ND 0.6] Compatible w/ All Popular Camera Lens Models - Walmart.com
Color Grad® Neutral Density .6 Filter - 46CGND6 – The Tiffen Company