DRITZ-Metal Class 66 Bobbins. For Singer models 66, 99, 101, 185, 192, 201, 247, 288, 327, 328, 329, 401, 403, 404, 413, 416, 418, 457, 476, 477, 478, 500, 717, 719, 814, 834, series 6100, 6500 7100 and other drop-in bobbin machines. This package contains four bobbins measuring 6/16in top to bottom. Imported.