Little rubber tube in puncture repair kits....why?

Ok, so I bought a puncture repair kit today, and I checked to see how much of whatever was in there, and then I saw the little rubber tube. Does anyone know what it’s for?

I can’t for the life of me figure out just what I’m supposed to do with it. Just what possible application could a small length of thin rubber tube have in repairing a puncture?

Can somebody please tell me?

-Keven out

It’s a replacement tube for the valve.
On older style tubes anyway.

Hey, a technical (kinda) question I managed to answer.
Will miracles never cease?