I replace a Shark Vacuum (DuoClean) with a Eureka upright. I saved the attachments because I had like 7 attachments for the Shark including rolling brush, under appliance cleaner, etc. that didn't come with the Eureka. The issue is they don't fit. I am looking for an adapter to make them work. The hose on the Eureka seems to be the same size as the attachment openings.

I went to two local big box stores and tried every plumbing part that looked like it might work as a coupler. None worked. Any vacuum specific adapters were for shop vacs. Any ideas?

As best as I can measure the new vacuum hose is 1.25 ID and 1.5 in OD and the older attachments are the same.

Most things on Amazon seem to be adapters rather than couplers.