Gardena coupling for 33mm (1G) threading. Used to connect garden hose to pumps etc. These larger threads are a little harder to come by than the regular gardena fittings.
The gardena part is a remix of another thingiverse thing which I downloaded but can't find anymore, so I can't pay tribute to the original creator.
Printed in two parts so the base is smooth and a diy cardboard gasket should seal it.
It also needs an o-ring. There's one on thingiverse, so try to print it out using flexible material.
Not sure if a printed o-ring would suffice though.