I created this so I can use the accessories (brush, crevice tool, etc.) for my 1-7/8" Home Depot Ridgid shop vac on my 2-½" Craftsman shop vac. I think the fittings are pretty standard across other brands of these sizes of shop vacs.

Using the “0.20mm Strength” preset profile (6 walls, 25% infill), the piece seems plenty strong enough even out of PLA. I added a 5mm brim for safety during printing since the bed surface area is pretty small.