One new rubber bobbin winder tire and tap in spool pin with felt. This is the most common size tire which was used on most vintage Singer machines, including the class 15, 66, 99, 127, 128, 192 Spartan & 201. *Depending on the outer diameter of your old tire, you may need to make a simple adjustment to your old Singer after installation to ensure the correct amount of friction is applied while in use. The spool pin will just need to be gently tapped in until snug.