Car Audio polystyrene Grommet 25mm centre bore

Installed a subwoofer under my boot/trunk liner and I had to drill a hole through the polystyrene sub layer, after drilling the hole I noticed it was a very messy finish which I wasnt happy with. I then designed a small grommet to hide the mess and has a thick thread pitch to ensure a nice tight fit. 

Grommet worked great in its application and a very simple print. 

If this has been useful for you, please feel free to boost or support my patreon, it helps me out a great deal and encourages me to make more designs moving forwards, Thank you for your time!