Thin ND fader is thin! Had been using this from one of my sponsor for the Photokina trip: Aurora Aperture, this is a prototype of their PowerXND Mark II, a pair of ND fader covering 1-11 stops. Just look at how thin it is even with a step-up ring! Even not that much thicker than a fixed ND. Excellent image quality for a variable ND too. #Sponsored but it is great stuff!