Polaroid Optics 67mm Neutral Density Filter [ND 0.6] Compatible W/ All Popular Camera Lens Models - Walmart.com
Amazon.com : NiSi 67mm Swift True Color ND-Vario | 1-5 Stops Variable Neutral Density Filter | Adjustable ND, True-to-Life Color, No Vignetting, Optical Glass with Nano Coating | Photography and Videography : Electronics