Here is how to use a Thetford Curve Porta Potti. I show the filling of the bowl and flushing.

Here is where you can get your own:
https://www.amazon.com/Thetford-92360-Porta-Portable-Toilet/dp/B006WPQNB2/ref=as_sl_pc_ss_til?tag=malimish-20&linkCode=w01&linkId=YVUZ324IQM2CI3YZ&creativeASIN=B006WPQNB2

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