Dust port expander for the Parkside (lidl) belt sander.
It was specifically designed to fit a Nilfisk rubber nozzle but may fit similar.
The port opening is 36mm across with a slight taper.
This does require support. I found it worked well with the nozzle opening on the bed and just placing support in the slot around the top.
This was printed in PLA but PETG or ABS may be better options.