Guaranteed to fit Singer sewing machine models:
18U122, 18U322, 20U, 20U73, 20U11, 20U12, 20U13, 20U31, 20U33, 20U42, 20U43, 20U51, 20U53, 20U62, 20U63, 20U73B, 20U83, 20U83B, 20UX142, 21U157KA, 212A141BA, 291U1, 291U3, 299U250W, 299U251W, 299U253SW, 299U253MW, 299U253LW, 491D200AA, 491D200GA, 491D300GA, 412U141AA, 412U141BA, 412U141GA, 412U541AA, 412U541BA, 412U541GA, 431F200A, 569U