Metal shuttle bobbins.
Singer 127 Singer 127-12 Singer 127-3 Vibrating Shuttle Singer 128 Singer 128-12 Singer 128-13 Singer 128-18 Singer 128-23 Singer 128-3 Vibrating Shuttle Singer 128-8 Singer 128k Singer 27 Vibrating Shuttle Singer 28 Vibrating Shuttle and more! Would any of these shuttle bobbins fit this machine? How do I know what size I need?