This is a three-part hose cuff that couples the 1-1/4" hose from my 1970s Eureka Canister vacuum cleaner to the metal end to which the accessories attach. The hose threads into the main part via reverse (left-handed) threads. The metal piece fits into a groove and the clamshell (second part) fits over that. Finally, a collar slips over the clamshell to hold everything in place. I used automotive gasket glue between the hose and the metal end; I used epoxy plastic glue to hold the clamshell in place, and then use a little super glue to make sure the retaining collar didn't slip back off.
I have included the Fusion 360 f3d file. This is a parameter-drive f3d file so you can do most modifications simply by entering new parameters, rather than editing the model itself.