Mysterious bobbin marked CWC
I picked up and old turquoise SM Accessories box at GW yesterday and found inside a few items. Some old needles, one marked HA, a Greist narrow hemmer foot, and three bobbins. The bobbins resemble Bernina bobbins as they are perforated top and bottom, but on the inside is stamped CWC and a circular design of some sort. Both sides have a slot for winding too.
So, my question is: what machine do these guys fit? Does any of this sound familiar to anyone out there?