This is a chair grommet for a Basscat boat. I have made the lip wider, and the walls a little thicker to help it hold up over time.
Inside Diameter = 68mm
Outside Diameter = 73mm
Flange Thickness = 5mm
Total Height = 25mm
If you are looking for other sizes, but in the same design, let me know and I can add them here.
Supports are not necessary, but can be used if your printer struggles with the inside and outside corner radius.