I've spent a bunch of time looking and haven't found what I need. I need a fitting that fits into the standard 2.25" opening on a shop vac. The other side I have 2 options. I can slip a 1-1/4 ID fitting over or a 1.5 OD fitting inside.
I bought what I thought I needed at Lowes and it turns out it fits OVER the 2.25" end of a vac hose. Rockler makes one that's 2.25 OD on one side but the other side is 1.25 ID so I'd have to use a 1-1/4 coupler which probably works but starts geting stupid expensive. I've found others with a 1.5 OD.