I created this to fit my Ridgid shop vac (with the standard 1.57 inch/40mm hose) to my DeWalt 7491RS table saw (with the standard 2.5 inch/64.5mm dust collection port). There are many other dust port adapters out there but I couldn't find one that was both the right size and sturdy, so I made my own.
It fits snuggly to both ports with no tape or adhesive needed. The walls are 2mm thick which actually makes the adapter very sturdy. I printed it with 100% infill in PLA.
The author hasn't provided the model origin yet.