The duct looks scary thin, but is quite strong and prints easily on an M2. In PLA 25% filled, it only uses 10g. It mounts using the same screws and nuts that came with the M2.Incidentally, yup, that is it being used to print a copy of itself in the first photo. Why? Well, I printed the first one before I had the attachment and the second one (as you can see) after. The second one is a much nicer print... which was the whole point of doing this. I actually have two M2s, so neither copy of this mount will go to waste. ;-)The photo of the cup is of http://www.thingiverse.com/thing:690176 , printed on my MakerGear M2 after installing the ducted fan mount. This is a tiny wine glass, with a long stem that's around 2.25mm diameter -- which would have sagged and probably caused a print failure with the standard fan mount. Printed in white PLA at 0.25mm, 8% fill (there's fill in the base, stem, and lower portion of the cup), 50mm/s.