My Singer 127 is a shuttle machine and will take the same standard sized bobbin winding tire as most of the other Singers. There seems to be many different sizes though. But since the winder is moveable you have a lot of leeway. Also since the rubber tires stretch, you have leeway there too.
Here's the Sew-Classic page for the bobbin winding tires {
http://www.shop.sew-classic.com/Bobb...-Tires_c16.htm }.
Jenny has included dimentions so you can find one that's closest to what you need. The one that fits the most Singers is the first one listed. I just got 10 of them in for a bunch of machines and stock.
Joe