The Fader ND filter is a life saver when shooting outdoors. Â I brings in variable neutral density exposure control while allowing you to maintain a constant aperture. Â The only problem was you needed to thread it on to your lens which can be a hassle if changing lenses. Well now there is a 4×4 option for the Fader ND which allows for the same rotating variable ND but will work with any size lens as long as you have a 4×4 mattebox to hold the filters.