I created this adapter to test some dust collection stuff for my shop. You should be able to print it without any supports. Do not use this in an active dust collection system unless you are very familiar with the fire/explosion hazards that can occur from static build up in such systems and have actively mitigated all of the risks. When I create my final version I plan on using some conductive filament I have to allow for grounding. I'm not sure if this will resolve this kind of issue, so if anyone knows I would really appreciate comments on it.