SINGER: 31-15 44 95 96 120U 121C 121D 188K 191D 195K 196K 241 251 281 366K 400W 402W 451K 491D 591D 600W 660A 691D 770D 771D 2191 2491D. USED for stitching in very close to zippers, buckles, cording, piping, etc.
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