This TPU grommet is designed for holes with a diamter of 31.5mm (though it might also work on 31-32mm holes, didn't try this) with a sheet thickness of 3mm. I used this grommet for the back panel of my Ikea LACK enclosure.
The grommet has been sliced in half, meaning you need to print the included parts twice for one grommet. Support is recommended for a clean surface finish.
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