O-Ring TPU Option for Nextruder MMU Modification

I didn't have an o-ring handy as I'm upgrading an old MMU2S so I created this simple model. 

You may have to slightly resize in the slicer to get it to fit just right over the gears, depending on your TPU material but I think it will do the job just fine. My nextruder is working fine and I don't see how filament could get through that seal with the TPU ring compressed against it.