This reversible spool pin is compatible with different sewing machine models depending on which end of the spool pin you insert into the machine.

The rounded (slightly tapered) end is equivalent to spool pin #172007 and the indented end is equivalent to spool pin #173571.

 compatible with Singer Sewing Machine Models: 327, 327K, 328, 329, 337, 338, 347, 348, 401, 403, 404, 413K, 413K13, 416K, 418, 457, 466, 476, 477, 478, 502, 507, 509, 513, 514, 518, 522, 527, 533, 534, 538, 6513, 6548 (For #172007 Rounded end)

 compatible with Singer Sewing Machine Models: 1247, 1263, 1802, 1803, 1812, 1852, 1853, 1862, 1872, 1873, 2302, 2303, 2304, 2313, 2330, 237, 239, 240, 242, 2430, 247, 247AP, 250, 2503, 2504, 2515, 252, 2530, 257, 258, 259, 285, 288, 290, 3101, 3102, 3103, 3105, 3314, 3317, 3343, 360, 362, 366, 367, 417, 476 Stylist, 476K Stylist, 6100, 6102, 6104, 6105, 6106, 6110, 6120, 6130, 6136, 6146, 6152, 6156, 6174, 6184, 7100, 8700 (For #173571 Indented end.)