7530 Radial to 40mm Axial Adaptor

I printed and installed the Tevo Black Widow cooling ducts by admodesi: https://www.thingiverse.com/thing:2251893
I am still not sure his ring duct is better than the “fang” style I designed several months ago, but it seems to be working well so far. The problem was that the 40mm axial fan was really noisy. I tried using several of my most powerful 40x20mm fans because I sometimes want maximum cooling, but they all made more noise than I prefer.
So, I drew up an adapter so I could use a 75m