The bobbin Doug (and I) use is the standard kind used by older Singer sewing machines with a horizontal bobbin holder. You can find actual Singer bobbins, but there are lots of cheaper no-name versions that work just as well. It was pretty much the standard of the industry for a long time. Pick up a 4 pack for $2 at any store with a sewing section. Even most Walmarts will have them back in the craft department.<br><br>Greg<br>(who sews on a 35+ year old Singer machine that still works great!)