Edit: I have uploaded a 60mm version too, but this is not tested. Hole distances are 50mm
I wanted an cool fan duct for my hero me gen3 setup to prevent debris and small fingers (aka kids) hitting the fan, but the ususal fan covers were either causing a significant increase in noise because most have struts and fins which cause interference or interfered with the hero me fans.
So I decided to design my own. As I use the dual 5015 hero me setup it had to fit that. I think it may add a tiny bit of noise, but I think it looks cool :)
dimensions: fits a 40x40mm fan. you need to replace the stock 10mm m3 screws with 20mm ones. They came with my 5015 fans so I designed the fan duct for them.