I need to buy an adapter to make my shop vac work with one of my hand tools. But as I'm shopping, I realize I'm not sure what exactly I need to buy. I'd like to understand how vacuum hose sizes are specified so that I can measure what I have.
For example: on my shop vac, the end of the hose measures 2-1/8"ID x 2-1/4"OD, and the end of the attachments measure 2-1/4"ID x 2-1/2"OD. What is the correct way to refer to the size of this hose?